SECURITY TARGET
FOR
ASCERTIA ADSS SERVER
SIGNATURE ACTIVATION MODULE (SAM)
Common Criteria version 3.1 revision 5
Assurance Level EAL 4+
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Table of Contents
1. ST Introduction............................................................................................................... 5
ST Overview............................................................................................................ 5
ST Reference.......................................................................................................... 5
TOE Reference ....................................................................................................... 6
TOE Overview......................................................................................................... 6
1.4.1. TOE Usage & Major Security Features............................................................. 9
1.4.2. TOE Type........................................................................................................10
1.4.3. Non-TOE Hardware/Software/Firmware..........................................................10
TOE Description.....................................................................................................12
1.5.1. Physical Scope of the TOE..............................................................................12
1.5.1.1. Delivery of the TOE .....................................................................................13
1.5.1.2. Roles & Available Functions ........................................................................13
1.5.1.3. Authentication & Authorisation.....................................................................14
1.5.1.4. Cryptographic Support.................................................................................14
1.5.1.5. Audit ............................................................................................................15
1.5.1.6. Trusted Communication...............................................................................15
1.5.2. TOE Life Cycle................................................................................................15
2. Conformance Claims.....................................................................................................17
2.1 Common Criteria Conformance Claim....................................................................17
2.2 Package Conformance Claim.................................................................................17
2.3 Protection Profile Conformance Claim....................................................................17
2.4 Protection Profile Conformance Rationale..............................................................17
2.4.1 Security Problem Definition .............................................................................17
2.4.2 Security Objectives .........................................................................................19
2.4.3 Security Functional Requirements...................................................................20
2.4.4 Security Assurance Requirements ..................................................................22
3. Security Problem Definition ...........................................................................................23
3.1 Assets ....................................................................................................................23
3.2 Subjects .................................................................................................................26
3.3 Threats...................................................................................................................27
3.3.1 Enrolment........................................................................................................27
3.3.2 Signer Management........................................................................................28
3.3.3 Usage .............................................................................................................28
3.3.4 System............................................................................................................30
3.4 Relation Between Threats & Assets .......................................................................31
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3.5 Organisational Security Policies .............................................................................32
3.6 Assumptions...........................................................................................................33
4. Security Objectives........................................................................................................35
4.1 Security objectives for the TOE ..............................................................................35
4.1.1 Enrolment........................................................................................................35
4.1.2 User Management...........................................................................................35
4.1.3 Usage .............................................................................................................36
4.1.4 System............................................................................................................37
4.2 Security Objectives for the Operational Environment..............................................37
4.2.1 Security Problem Definition & Security Objectives...........................................39
4.2.2 Rationale for the Security Objectives...............................................................45
4.2.2.1 Threats & Objectives ...................................................................................45
4.2.2.2 Organizational Security Policies & Objectives..............................................47
4.2.2.3 Assumptions & Objectives ...........................................................................48
5. Extended Components Definitions ................................................................................49
5.1 Class FCS: Cryptographic Support.........................................................................49
5.1.1 Generation of Random Numbers (FCS_RNG).................................................49
6. Security Requirements ..................................................................................................51
6.1 Use of requirement specifications...........................................................................51
6.2 Subjects, Objects and Operations ..........................................................................51
6.3 SFRs overview.......................................................................................................53
6.4 Security Functional Requirements..........................................................................55
6.4.1 Security Audit (FAU)........................................................................................55
6.4.2 Cryptographic Support (FCS) ..........................................................................57
6.4.3 User Data Protection (FDP).............................................................................63
6.4.4 Identification & Authentication (FIA) ................................................................80
6.4.5 Security Management (FMT)...........................................................................85
6.4.6 Protection of the TSF (FPT) ............................................................................89
6.4.7 Trusted Paths/Channels (FTP)........................................................................91
6.5 Security Requirements Rationale ...........................................................................94
6.5.1 Security Requirements Coverage....................................................................94
6.6 SFR Dependencies ..............................................................................................100
6.7 Security Assurance Requirements .......................................................................103
7. TOE Summary Specification .......................................................................................105
7.1 TOE Security Functions .......................................................................................105
7.1.1 User Roles & Authentication (TSF_AUTH)....................................................105
7.1.2 Key Security (TSF_CRYPTO) .......................................................................106
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7.1.3 Access and information flow control (TSF_CTRL) .........................................106
7.1.4 Data protection (TSF_DP).............................................................................110
7.1.5 Audit (TSF_AUDIT) .......................................................................................111
7.1.6 Communication protection (TSF_COMM)......................................................112
7.2 Fulfilment of the SFRs..........................................................................................112
7.2.1 Security Requirements Coverage..................................................................113
8. Glossary and Acronyms ..............................................................................................114
8.1 Acronyms.............................................................................................................114
9. Bibliography ................................................................................................................115
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1. ST Introduction
ST Overview
This Security Target (ST) document defines the security objectives and requirements, as
well as the scope of the Common Criteria evaluation of Ascertia ADSS Server Signature
Activation Module (SAM) product.
The Target of Evaluation (TOE) is the Ascertia ADSS Server SAM software product, which
consists of the following main software components:
 ADSS Server SAM Service – handles user registration and signing requests through
its API interface
 ADSS Server SAM Admin Console – allows trusted administrators to configure the
product and perform maintenance / housekeeping tasks
 ADSS Server SAM Core – performs automated background tasks
and the following non-software components:
 Operational User Guidance [23]
 Preparation Procedure [24]
The TOE is delivered within a tamper-protected hardware device to ensure a secure
execution environment. The TOE provides a remote Qualified Electronic Signatures and
Seals (referred to collectively as QES) service according to eIDAS Regulation No 910/2014
[8] at Sole Control Assurance Level 2 (SCAL2) according to EN 419 241-1 [6].
This ST addresses the following advanced security mechanisms: -
 Remote QES according to eIDAS Regulation No 910/2014 [8]; and
 Sole Control Assurance Level 2 (SCAL2) according to sec. 5.4 of EN 419 241-1 [6].
ST Reference
This ST is identified by the following unique reference: -
ST Title: ASE: Security Target
ST Version V18
ST Date: 2018-10-01
ST Author: Ascertia Limited
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TOE Reference
The TOE is identified by the following unique reference: -
TOE Name Ascertia ADSS Server Signature Activation Module
(SAM) product
TOE short name ADSS Server SAM
TOE Version v6.0
Evaluation Criteria Common Methodology for Information Technology
Security Evaluation, Evaluation Methodology;
CCMB-2017-04-004, Version 3.1, Revision 5, April
2017
Protection Profile(s) EN 419 241-2 [5]
Evaluation Assurance Level EAL 4 augmented by AVA_VAN.5
Developer Ascertia Limited
Evaluation Sponsor Ascertia Limited
Evaluation Facility CCLab Software Laboratory
Certification Body OCSI
Certification ID
TOE Overview
The TOE addressed in this ST is the Ascertia ADSS Server Signature Activation Module
(SAM) product.
The Ascertia ADSS Server SAM product is a Trustworthy System Supporting Server Signing
(TW4S) that offers remote digital signature services. It ensures that the Signer’s signing
key or keys are only used under the sole control of the Signer and only used for the
intended purpose.
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The Ascertia ADSS Server SAM remote signing solution consists of a local and a remote
environment as illustrated below.
Signer can initiate a signing transaction by interacting through a Business Application.
Signers interact with the Business Application normally via a web browser. To sign a
document, the Signer has to use a mobile app, named the Go>Sign Mobile app, on a
registered mobile device to securely authorise the server-side signing action using a
trusted protocol referred to as the Signature Activation Protocol (SAP).
To be able to authorise a remote signature, the mobile device is first registered with the
TOE against the user’s (Signer) account. The signing authorisation is at Sole Control
Assurance Level 2 (SCAL2) according to EN 419 241-1 [6] for qualified signatures.
During a remote signing operation, the Signer will be asked to launch the Go>Sign Mobile
app to download the authorisation request for the user to view and authorise.
In order for the Go>Sign Mobile app to sign the authorisation response, the Signer must
authenticate to the mobile device in order to access the authorisation key held in the
mobile device’s embedded Secure Element/Enclave (SE). The user authenticates to the
mobile device using iOS/Android biometric techniques (e.g. TouchID or FaceID) or the
mobile device passcode.
After the successful authentication of the Signer, the Go>Sign Mobile app digitally signs
the authorisation response XML using the Authorisation Key held in the mobile device’s
SE. The signed authorisation response is referred to as the Signature Activation Data (SAD).
The SAD represents 2-factor authentication because it relies on the fact that the user must
use their registered mobile device (“something that the user has”) and authenticate to the
mobile device using either biometric authentication (“something the user is”) or the
mobile device PIN (“something the user knows”).
The signed SAD value cryptographically binds together:
 The Signer’s identity and authentication (via the signature on the SAD value)
 The Business Application ID which requested the signature
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 The unique transaction ID
 The User’s remote Signing Key ID held within the TOE
 The hash of the data to be signed remotely (DTBS/R)
 Random salt information to prevent replay attacks
 Mobile device ID used to create the SAD
 Validity date/time for the authorisation response
Each of the above elements within the signed SAD are verified by the TOE before allowing
the Signer’s key to be used for signing the data identified in the SAD. Note the SAD also
contains some additional detailed information not described above.
The TOE is responsible for maintaining the details of: -
 Registered users (signers);
 Authorised mobile devices;
 Authorisation requests/responses; and
 Current statuses of the above described features.
In addition to this, the TOE cryptographically verifies every signed authorisation response
XML (SAD) before the remote signing is performed by the Ascertia ADSS Server SAM. The
signing key is activated in a Cryptographic Module (CM).
The Ascertia ADSS Server SAM is located within its own tamper protected environment
referred to as the ADSS Server SAM appliance. The CM is located inside the appliances
tamper protected environment. The TOE is connected to the CM through a trusted
channel. The CM is shipped as an embedded module inside the ADSS Server SAM
appliance, although even in this case it is important to note that the CM has its own tamper
protected environment and the same trusted channel is used for the communication as if
it was an external device.
SAD verification means that the ADSS Server SAM checks the following bindings:
 The signature on the SAD can be verified by the authorisation certificate belonging
to the Signer for this registered mobile device (note the Signer may multiple
devices registered for remote authorisation purposes each with their own
authorisation key pair and certificate)
 The Signer’s ID in the SAD is correct
 The Business Application ID is correct
 The unique transaction ID is correct
 The remote Signing Key ID is available and belongs to this Signer
 The hash of the document (DTBS/R) matches that which the Business Application
is requesting to sign on behalf of the user
 The random salt information in the SAD matches that provided in the authorisation
request message to ensure this is not a replay
 The mobile device ID is recognised as a registered device for this Signer
 The validity period in the response is not expired according to current date/time
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Note the TOE also various some additional items from the SAD which are not mentioned
above.
The following Figure shows the main components of the ADSS Server SAM solution in more
detail.
It is important to note that all API interactions with the ADSS Server SAM must be conducted
through the ADSS RAS Service. This means from the perspective of the TOE, the ADSS RAS Service
is considered as a Business Application. The TOE authenticates the ADSS RAS Service as a Business
Application before allowing access to its services. Throughout this document the term Business
Application applies to the ADSS RAS Service as well.
1.4.1. TOE Usage & Major Security Features
The Ascertia ADSS Server SAM solution ensures that the remote Signer has sole control of
his signing keys at Sole Control Assurance Level 2 (SCAL2) according to EN 419241-1 [6] for
qualified signatures. This means that the signature operation needs to be authorised,
which is done using the Go>Sign Mobile app.
The TOE functionality includes but is not limited to: -
 Maintain the details of registered signers;
 Maintain the details of registered mobile devices;
 Generate authorisation requests;
 Verify the signed authorisation response XML (SAD);
 Generate the signing key pair in the CM; and
 Activate the signing key within the CM.
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The Signer, using the Go>Sign Mobile app, communicates with the TOE via RAS Service to
submit the SAD. The SAD binds together the Signer authentication with the signing key
and the data to be signed, i.e. DTBS/R.
To avoid direct communication, the Go>Sign Mobile app securely communicate with the
RAS Service (c.f. sec. 1.4.3), which then communicates with the TOE during both user
registration as well remote signing operations.
The TOE can be used in High Availability by having multiple ADSS Server SAM appliances
running in parallel behind a load-balancer. Replication of the cryptographic keys from one
ADSS Server SAM appliance to the other is supported (including the replication or the keys
managed by the embedded EN 419 221-5 compliant HSM).
1.4.2. TOE Type
The TOE is the Ascertia ADSS Server SAM.
The TOE is a software component, which implements the SAP. The TOE runs in a tamper
protected environment that is connected to the CM via a trusted channel.
The TOE uses the SAD from the Signer to activate the corresponding signing key for use in
a CM.
The TOE and the CM are together the Qualified Signature Creation Device (QSCD).
1.4.3. Non-TOE Hardware/Software/Firmware
The following hardware, firmware and software are supplied by the IT environment, and
are therefore excluded from the TOE boundary: -
1. ADSS RAS Service
The ADSS RAS Service provides
 the required API interface towards the Business Application to: -
1. Register the users, i.e. Signers;
2. Send hash signing requests;
3. Check the status of pending signing requests; and
4. Retrieve the signed hash.
 the required API interface towards the Go>Sign Mobile app to: -
1. Allow user mobile registration (including authorisation key pair
generation and certification)
2. Allow Signer (user) to download authorisation request XML into the
Go>Sign Mobile app;
3. Send the signed authorisation response XML (SAD) from Go>Sign
Mobile app to the TOE.
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2. Go>Sign Mobile app
The Go>Sign Mobile app is the Signer’s Interaction Component (SIC). It is used
locally by the Signer to communicate with the Ascertia ADSS Server SAM solution.
The Go>Sign Mobile app authorises the remote signing actions by digitally signing
authorisation responses using an authorisation key pair held securely in the
mobile device’s Secure Hardware Element.
3. Database
The Ascertia ADSS Server SAM uses an RDBMS to store the details of: -
1. Registered users;
2. Registered mobile devices;
3. Authorisation requests;
4. Authorisation responses; and
5. Signing transaction logs.
The integrity of the data stored in any of the Ascertia ADSS Server SAM tables is
protected by sequenced HMAC. The HMAC symmetric key is held in a CM.
4. Cryptographic Module
The cryptographic key management and signing cryptographic operations occur in
a CM which shall be certified according to EN 419 221-5 [7]. Note the CM is
embedded inside the ADSS Server SAM appliance. The ADSS Server SAM
authenticates and authorises each signing operation with the CM using a secure
protocol which meets the requirements of the standard EN 419 221-5 [7].
5. Business Application
The Business Application can be a server-side or desktop application to which a
Signer interacts. The Signer (user) registration process is carried out by the
Business Application on behalf of the user. The Business Application initiates
different operations in the TOE, for example: -
1. Create Signers (users);
2. Create signing key pairs;
3. Send the hash for signing;
4. Check status of pending signing requests; and
5. Retrieve signed hashes.
As explained earlier all Business Applications interactions with the TOE are
conducted through the ADSS RAS Service. From the perspective of the TOE the
ADSS RAS Service itself is the Business Application.
The ADSS RAS Service is registered as client using the ADSS Server SAM Admin
Console. It is identified by a “Client ID” and authenticated using a TLS client
certificate. The Business Application provides the document hash, i.e. DTBS/R, in
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the signing request to the ADSS RAS Service which passes it to the TOE for
signature.
TOE Description
The ADSS Server SAM consists of the three components named:
1. ADSS Server SAM Service
ADSS Server SAM Service provides different web services to perform various operations e.g.
User Account Registration, user key enrollment, user mobile device registration,
transaction/hash signing etc.
2. ADSS Server SAM Admin Console
ADSS Server SAM Admin Console allows administrators to configure the product, e.g. define
access control, signer/user management, signer device management, configuring crypto
source i.e. HSM etc.
3. ADSS Server SAM Core
ADSS Server SAM Core performs various background tasks e.g. Logs archiving, DB
monitoring, HSM monitoring etc.
1.5.1. Physical Scope of the TOE
The physical boundary of the TOE is the tamper protected hardware fulfilling
requirements of ISO/IEC 19790 [22] Security Level 3. The tamper protected hardware is
also part of the TOE but not everything inside is part of the TOE. The operating system,
application server, HSM, database etc. do not belong to the TOE. The TOE consists of the
tamper protected hardware and the software components inside ADSS Server SAM
logical boundary on the figure above.
The TOE can be configured using the ADSS Server SAM Admin Console. There are
multiple possible configuration of ADSS Server SAM but only a specified configuration is
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certified which uses the Common Criteria certified-mode security settings and a certified
CM. The configuration is described in AGD Guidance documents.
1.5.1.1. Delivery of the TOE
1. Ascertia will provide the Ascertia ADSS Server SAM software to its authorised SAM
distributor
2. The software is encrypted using zip password-protection and uploaded to a secure FTP
area hosted by Ascertia. Credentials for accessing the FTP area will be provided to the
authorised SAM distributor securely using encrypted email. The email will also contain
the cryptographic checksum of the uploaded software. The same email will also
contain details of the customer to whom the ADSS Server SAM Appliance is to be
shipped.
3. Ascertia will provide details of how to verify the cryptographic checksum to its SAM
distributor
4. The SAM distributor verify the checksum on the ADSS Server SAM software after
downloading it from the Ascertia FTP site
5. The SAM distributor will construct the ADSS Server SAM Appliance by installing the
required components, i.e.:
a. operating system,
b. database,
c. the approved EN 419 221-5 certified HSM (by contacting the HSM vendor and
ensuring its securely delivery according to its defined procedures)
6. Then checksum-verified ADSS Server SAM software will be placed inside the appliance
by the SAM distributor.
7. The SAM distributor will ensure that the SAM Appliance is properly sealed/protected
and once done securely deliver the SAM appliance to the customer and inform Ascertia
and the customer about the status (ETA)
8. The end-customer who receives the appliance will ensure the ADSS Server SAM
appliance seals have not been tampered with.
9. The ADSS Server SAM software will then installed by the end-customer following the
defined deployment documentation.
1.5.1.2. Roles & Available Functions
The TOE maintains the following roles: -
1) Privileged Users. There are two types of Privileged Users who can perform TOE
specific operation through either the ADSS Server SAM Admin Console or the
externally available ADSS Server SAM API:
a. Ascertia ADSS Server SAM Operators (Operators): They access the
Ascertia ADSS Server SAM Admin Console to perform different TOE specific
operations, e.g. configuring communication with the HSM, etc. These
trusted Operators are created in ADSS Server SAM Admin Console and
each operator is identified by an “Operator ID”.
b. Business Applications: These access the TOE via APIs provided by RAS
service to perform different TOE specific operations. On one hand they
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manage Signers (User Module) and the other, they act as Signature
Creation Application (SCA). Business application are identified by their
“Client ID”.
2) Unprivileged Users.
a. Signers: These are able to request remote signing operations by interacting
with above Business Applications and then authorise these operations
using the Ascertia Go>Sign mobile app to supply the required authorisation
data
1.5.1.3. Authentication & Authorisation
The following authentication and authorisation processes occur: -
 Operators: They must logon to the Ascertia ADSS Server SAM using TLS client
certificates before being allowed to perform any activity on the Ascertia ADSS
Server SAM Admin Console. Operator TLS client certificates and associated private
keys should be stored on a secure smart card/USB token thereby providing an
extra layer of security for the private key plus two-factor authentication of the
operator. The revocation status of Ascertia ADSS operator TLS certificates can also
be checked at the time of logon by configuring this in Ascertia ADSS Server SAM
Admin Console. However, it is recommended that operators’ accounts are also
immediately updated on Ascertia ADSS Server SAM at the time a certificate is
revoked. The Ascertia ADSS Server SAM Admin Console ensures that access to
system objects is strictly controlled. Users are first identified and authenticated as
explained above, and once this process is complete and the user has successfully
logged in, then access to system objects is controlled according to the user’s role.
Each role has a definition of which system objects it can access, and the type of
access, e.g. read only, or edit/create/delete.
 Business Applications: They must be authenticated before accessing the Ascertia
ADSS Server SAM APIs. The business applications must also authenticate using
their respective TLS client certificate because all the communication is via
mutually authenticated TLS channel. Note here the term Business Application
refers to the ADSS RAS Service through which all business app interactions are
conducted with the TOE.
 Signer: They are identified by the user ID and authenticated during device
registration by two OTPs sent to the user’s registered mobile number and email
address. During the signing operation, Signers are identified via their user ID and
authenticated by the signed authorisation response XML (SAD).
1.5.1.4. Cryptographic Support
The TOE does not perform cryptographic operations for its users (Signers): explicitly it
does not generate/store/destroy, export/import, backup/restore, or use user key. The
TOE invokes the CM with appropriate parameters whenever a cryptographic operation
for the Signer is required, i.e. to authorise usage of the Assigned Key.
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The TOE uses different infrastructure keys to protect its stored files and database
records, and data transmitted or received via communication channels.
1.5.1.5. Audit
The TOE audits all security related events. All the audit records produced as a result of
the TOE operator actions or the API requests from business applications are stored in
Ascertia ADSS Server SAM database. The audit records do not include any data which
allows the retrieval/decipherment of confidential data.
1.5.1.6. Trusted Communication
The TOE implements and enforces the following trusted communication methods and
protocols: -
 Operators: Ascertia ADSS Server SAM Operators (Privileged Users) access the
Ascertia ADSS Server SAM Admin Console GUI over a mutually authenticated TLS
v1.2 channel.
 ADSS RAS Service: ADSS RAS Service communicates with TOE using mutually
authenticated TLS v1.2 channel.
 CM: The TOE communicates with CM using vendor specific APIs. User passwords
do not travel on this channel. This communication with the CM is enforced by the
CM to be secure, authenticated and protected from replay attacks, i.e. the CM
meets the requirements of EN 419 221-5 Protection Profile and is certified to
Common Criterial EAL4+ level.
 Go>Sign Mobile app: The Go>Sign Mobile app (SIC) does not connect to the TOE
but via the ADSS RAS Service. The Go>Sign mobile app connects to the ADSS RAS
service over server-authenticated TLS v1.2 channel. The ADSS RAS Service then
connects with the TOE as explained above.
The communication between the Signer and the TOE for authenticating and authorising
the remote signature (using Go>Sign Mobile app) is conducted through the ADSS RAS
Service as explained is based on the Signature Activation Protocol (SAP). The SAP is
protected against replay, bypass and forgery attack, using a salt (random value to avoid
replay attack), a validity period and the PKCS#1 authorization signature of the Signer. The
SAP provides confidentiality for all sensitive transmitted data and integrity protection for
all transmitted data, including the authentication and authorisation data and DTBS/R.
1.5.2. TOE Life Cycle
The TOE life cycle consists of successive phase for development, production, preparation
and operational use.
1. Development: The TOE developer develops the TOE application and its guidance
documentation using any appropriate guidance documentation for components
working within the TOE physical boundary, including the CM.
2. Delivery: The TOE is securely delivered from the TOE developer to the TSP.
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3. Installation and configuration: The TSP installs and configures the TOE with the
appropriate configuration and initialisation data.
4. Operational phase: In operation, the TOE can be used by Operators to create other
Privileged Users (Operators or Business Applications) and by Business Applications to
register Signers. Operators can maintain TOE configuration. Business Applications can
manage Signers accounts and generate signature keys for a Signer. Only Business
Applications can supply the data to be signed to the TOE and only Signers can
authorise signature creation from their registered mobile devices using the Go>Sign
Mobile app.
The TOE end-of-life is out of the scope of this document.
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2. Conformance Claims
2.1Common Criteria Conformance Claim
This ST claims conformance to: -
 Common Criteria for Information Technology Security Evaluation Part 1:
Introduction and General Model; CCMB-2017-04-001, Version 3.1, Revision 5,
April 2017 [1].
 Common Criteria for Information Technology Security Evaluation Part 2:
Security Functional Components; CCMB-2017-04-002, Version 3.1, Revision 5,
April 2017 [2].
 Common Criteria for Information Technology Security Evaluation Part 3:
Security Assurance Requirements; CCMB-2017-04-003, Version 3.1, Revision 5,
April 2017,[3].
as follows: -
Part 2 extended; and
Part 3 conformant.
The following must be considered: -
 Common Methodology for Information Technology Security Evaluation,
Evaluation methodology; CCMB-2017-04-004, Version 3.1, Revision 5, April
2017, [4].
2.2Package Conformance Claim
This ST claims conformance to: -
 EAL 4 assurance package augmented by AVA_VAN.5 defined in the CC Part 3 [3].
2.3Protection Profile Conformance Claim
This ST claims strict conformance to: -
 EN 419 241-2: Trustworthy Systems Supporting Server Signing Part 2: Protection
Profile (PP) for QSCD for Server Signing [5].
2.4Protection Profile Conformance Rationale
2.4.1 Security Problem Definition
This ST claims strict conformance to the prEN 419241-2:2017 PP [5]. The parts of the TOE
listed in this PP correspond to the ones listed in section 1.4.1 of this ST.
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The security problem definition includes the assets, the subjects, the assumptions, the
threats and the organizational security policies of the PP.
The following tables demonstrates that this ST contains all assumptions, threats and
organisational security policies listed in prEN 419241-2:2017 PP [5].
Table 2-1 Source of Assumptions
Assumptions 419241-2:2017 PP [5] Added by this ST
A.PRIVILEGED_USER x
A.SIGNER_ENROLMENT x
A.SIGNER_AUTHENTICATION_DATA_PROTECTION x
A.SIGNER_DEVICE x
A.CA x
A.ACCESS_PROTECTED x
A.AUTH_DATA x
A.TSP_AUDITED x
A.SEC_REQ x
A.CERTIFICATION_AUTHORITY x
Table 2-2 Source of Threats
Threats 419241-2:2017 PP [5] Added by this ST
ENROLMENT
T.ENROLMENT_SIGNER_IMPERSONATION x
T.ENROLMENT_SIGNER_AUTHENTICATION_DATA_
DISCLOSED
x
T.SVD_FORGERY x
SIGNER MANAGEMENT
T.ADMIN_IMPERSONATION x
T.MAINTENANCE_AUTHENTICATION_DISCLOSE x
USAGE
T.AUTHENTICATION_SIGNER_IMPERSONATION x
T.SIGNER_AUTHENTICATION_DATA_MODIFIED x
T.SAP_BYPASS x
T.SAP_REPLAY x
T.SAD_FORGERY x
T.SIGNATURE_REQUEST_DISCLOSURE x
T.DTBSR_FORGERY x
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Threats 419241-2:2017 PP [5] Added by this ST
T.SIGNATURE_FORGERY x
SYSTEM
T.PRIVILEGED_USER_INSERTION x
T.REFERENCE_PRIVILEGED_USER_AUTHENTICATION_
DATA_MODIFICATION
x
T.AUTHORISATION_DATA_UPDATE x
T. AUTHORISATION_DATA _DISCLOSE x
T.CONTEXT_ALTERATION x
T.AUDIT_ALTERATION x
T.RANDOM x
Table 2-3 Source of Organisational Security Policies
Organisational Security Policies 419241-2:2017 PP [5] Added by this ST
OSP.RANDOM x
OSP.CRYPTO x
2.4.2 Security Objectives
The security objectives of prEN 419241-2:2017 PP [5] are included in this ST.
No additional security objectives were added by this ST.
Table 2-5 Source of Security objectives
419241-2:2017 PP [5] Added by this ST
Security Objectives for the TOE
OT.SIGNER_PROTECTION x
OT.REFERENCE_SIGNER_AUTHENTICATION_DATA x
OT.SIGNER_KEY_PAIR_GENERATION x
OT.SVD x
OT.PRIVILEGED_USER_MANAGEMENT x
OT.PRIVILEGED_USER_AUTHENTICATION x
OT.PRIVILEGED_USER_PROTECTION x
OT.SIGNER_MANAGEMENT x
OT.SAD_VERIFICATION x
OT.SAP x
OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION x
OT.DTBSR_INTEGRITY x
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419241-2:2017 PP [5] Added by this ST
OT.SIGNATURE_INTEGRITY x
OT.CRYPTO x
OT.RANDOM x
OT.SYSTEM_PROTECTION x
OT.AUDIT_PROTECTION x
Security Objectives for the operational environment
OE.SVD_AUTHENTICITY x
OE.CA_REQUEST_CERTIFICATE x
OE.CERTIFICATE_VERFICATION x
OE.SIGNER_AUTHENTICATION_DATA x
OE.DELEGATED_AUTHENTICATION x
OE.DEVICE x
OE.ENV x
OE.CRYPTOMODULE_CERTIFIED x
OE.TW4S_CONFORMANT x
2.4.3 Security Functional Requirements
The functional requirements described in section 6 of this ST include all SFRs from prEN
419241-2:2017 PP [5].
Iterations and changes to the SFRs, with respect to prEN 419241-2:2017 PP [5], are listed
in this table. These changes do not lower TOE security.
Table 2-6 Source of Security functional requirements
Security Functional Requirement 419241-2:2017 PP [5] Changes by this ST
Security Audit
FAU_GEN.1. x
FAU_GEN.2 x
Cryptographic Support
FCS_CKM.1 x iterated to */RSA,
*/ECDSA, */AES
FCS_CKM.4 x
FCS_COP.1 x iterated to
*/DIG_SIG_GEN,
*/DIG_SIG_VER,
*/HASH, */HMAC,
*/ENC
FCS_RNG.1 x
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Security Functional Requirement 419241-2:2017 PP [5] Changes by this ST
User Data Protection
FDP_ACC.1/Privileged User Creation x added refinement
FDP_ACF.1/Privileged User Creation x added refinement
FDP_ACC.1/Signer Creation x added refinement
FDP_ACF.1/ Signer Creation x added refinement
FDP_ACC.1/Signer Key Pair Generation x added refinement
FDP_ACF.1/Signer Key Pair Generation x added refinement
FDP_ACC.1/Signer Maintenance x added refinement
FDP_ACF.1/Signer Maintenance x added refinement
FDP_ACC.1/Signer Key Pair Deletion x added refinement
FDP_ACF.1/Signer Key Pair Deletion x added refinement
FDP_ACC.1/Supply DTBS/R x added refinement
FDP_ACF.1/Supply DTBS/R x added refinement
FDP_ACC.1/Signing x
FDP_ACF.1/Signing x
FDP_ACC.1/TOE Maintenance x added refinement
FDP_ACF.1/TOE Maintenance x added refinement
FDP_ETC.2/Signer x
FDP_IFC.1/Signer x added refinement
FDP_IFF.1/Signer x added refinement
FDP_ETC.2/ Privileged User x
FDP_IFC.1/Privileged User x added refinement
FDP_IFF.1/Privileged User x added refinement
FDP_ITC.2/Signer x
FDP_ITC.2/ Privileged User x
FDP_UCT.1 x
FDP_UIT.1 x
Identification and Authentication
FIA_AFL.1 x iterated to */BA,
*/Signer
FIA_ATD.1 x
FIA_UAU.1 x added refinement
FIA_UAU.5/Signer x
FIA_UAU.5/Privileged User x added refinement
FIA_UID.2 x
FIA_USB.1 x added refinement
Security Management
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Security Functional Requirement 419241-2:2017 PP [5] Changes by this ST
FMT_MSA.1/Signer x
FMT_MSA.1/Privileged User x
FMT_MSA.2 x
FMT_MSA.3/Signer x added refinement
FMT_MSA.3/Privileged User x added refinement
FMT_MTD.1 x added refinement
FMT_SMF.1 x
FMT_SMR.2 x added refinement
Protection of the TSF
FPT_PHP.1 x
FPT_PHP.3 x
FPT_RPL.1 x
FPT_STM.1 x
FPT_TDC.1 x
Trusted Path/Channels
FTP_TRP.1/SSA x added refinement
FTP_TRP.1/SIC x added refinement
FTP_ITC.1/CM x
2.4.4 Security Assurance Requirements
The minimum package of security assurance requirement allowed for conformance to
prEN 419241-2:2017 PP [5] is EAL 4 augmented with AVA_VAN.5.
This ST claims conformance to EAL 4 augmented by AVA_VAN.5. Therefore, the afore-
described requirement is met and with respect to prEN 419241-2:2017 PP [5].
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3. Security Problem Definition
3.1Assets
The TOE has the following assets, which are to be protected in integrity and confidentiality
as described below. The TOE must ensure that whenever an asset is persisted outside the
TOE, the TOE has performed the necessary cryptographic operations to enforce
confidentiality and detect if an asset has been modified. Access control to TOE assets
outside the TOE are to be enforced by the environment.
R.Signing_Key_Id: The signing key is the private key of an asymmetric key pair used to
create a digital signature under the R.Signer’s sole control. The signing key can only be
used by the CM. The TOE uses the asset R.Signing_Key_Id, which identifies a signing key in
the CM. The binding of the R.Signing_Key_Id with R.Signer shall be protected in integrity.
Application Note 1 (Application Note 1 from [5], refined by the ST Author)
The integrity and confidentiality of the signing key and the link between the
R.Signing_Key_Id and the signing key is the responsibility of the CM. The TOE ensures that
only the R.Signer can use the signing key under their sole control. This is achieved by
designing the TOE to conform to the requirements of Level 2 sole control described in [6].
R.Authorisation_Data: is data used by the TOE to activate a signing key in the CM. The
signing key is identified by R.Signing_Key_Id. In ADSS Server SAM case
R.Authorisation_Data is an authorisation key pair hold by the TOE.
It shall be protected in integrity and confidentiality.
Application Note 2 (Application Note 2 from [5], refined by the ST Author)
The R.Authorisation_Data is used by the CM to activate a signing key. The TOE holds an
authorisation key pair which acts as the R.Authorisation_Data. To ensure the
confidentiality, the authorisation private key is stored in encrypted form in the Ascertia
ADSS Server SAM database. HMAC ensures the integrity of the database records.
R.SVD: signature verification data is the public part, associated with the signing key, to
perform digital signature verification. The R.SVD shall be protected in integrity.
The TOE uses a CM for signing key pair generation. As part of the signing key pair
generation, CM provides the TOE with R.Signing_Key_Id and R.SVD. The TOE provides the
R.SVD to the ADSS RAS Service (SSA) for further handling for the key pair to be certified.
The integrity of the R.SVD is ensured through the use of a digital certificate.
R.DTBS/R: set of data which is transmitted to the TOE for digital signature creation on
behalf of the R.Signer. The DTBS/R is transmitted to the TOE. The R.DTBS/R shall be
protected in integrity. The transmission of the DTBS/R(s) to the TOE shall require the
sending party - Signer or Privileged User - to be authenticated.
Application Note 3 (Application Note 3 from [5])
The confidentiality of the R.DTBS/R is not required by eIDAS Regulation No 910/2014 [8].
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R.SAD: SAD is a set of data involved in the SAP, which activates the signature creation data
to create a digital signature under the R.Signer’s sole control. The R.SAD must combine: -
 The R.Signer’s strong authentication as specified in EN 419 241-1 [6].
 If a particular key is not implied (e.g. a default or one-time key) a unique reference
to R.Signing_Key_Id.
 A given R.DTBS/R.
The R.SAD shall be protected in integrity and confidentiality.
Application Note 4 (Application Note 4 from [5], refined by the ST Author)
Applied. The authorisation response XML is digitally signed by the Go>Sign Mobile app
using an authorisation key held on the mobile device’s secure element under the control
of the Signer. The authorisation signature value is appended to the authorisation response
XML under the <Signature> element. There is no confidential data contained in the
authorisation response XML, hence the confidentiality requirement is not applicable. The
confidentiality requirement is considered fulfilled.
Application Note 5 (Application Note 5 from [5])
The R.SAD may include some or all authentication factors or evidence from other systems
that some or all authentication factors have been verified.
Application Note 6 (Application Note 6 from [5], refined by the ST Author)
The unique reference to R.Signing_Key_Id in the R.SAD is information obtained from the
R.Signer’s authentication.
R.Signing_Key_Id is <CertificateID> of the certificate assigned to the R.Signer.
R.Signature: is the result of the signature operation and is a digital signature value.
R.Signature is created on the R.DTBS/R using R.Signing_Key_Id by the CM under the
R.Signer’s control as part of the SAP. The R.Signature shall be protected in integrity. The
R.Signature can be verified outside TOE using R.SVD.
R.Audit: is an audit record that contains a log of events, which require audit. The logs are
produced by the TOE and stored externally. The R.Audit shall be protected in integrity.
R.Signer: is a TOE subject containing the set of data that uniquely identifies the Signer
within the TOE. The R.Signer shall be protected in integrity and confidentiality.
Application Note 7 (Application Note 7 from [5])
It is only within the TOE the R.Signer needs to be unique. It is not the responsibility of the
TOE to establish a connection between the R.Signer and the signer’s identity. The Signer
is said to own the R.Signer object which uniquely identifies him within the TOE.
Application Note 8 (Application Note 8 from [5])
The R.Signer can include references to zero, one or several R.Signing_Key_Ids and R.SVDs.
Application Note 9 (Application Note 9 from [5], refined by the ST Author)
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The R.Signer does not require encrypted data then the confidentiality requirement is considered
fulfilled.
R.Reference_Signer_Authentication_Data: is the set of data used by TOE to authenticate
the R.Signer. It contains all the data (OTP device serial number, phone numbers, protocol
settings, etc.) and keys (device, verification, etc.) used by the TOE to authenticate the
R.Signer. This may include a SVD or certificate to verify an assertion provided as a result of
delegated authentication. In ADSS Server SAM case the
R.Reference_Signer_Authentication_Data is the mobile device id and the public key
certificate which can verify the signature on SAD.
The R.Reference_Signer_Authentication_Data shall be protected in integrity and
confidentiality.
Application Note 10 (Application Note 10 from [5])
The R.Reference_Signer_Authentication_Data is used by the TOE to authenticate the
R.Signer, and the R.Authorisation_Data is used by the TOE to activate a signing key in the
CM.
Application Note 11 (Application Note 11 from [5], refined by the ST Author)
The integrity of the records stored in Ascertia ADSS Server SAM database is protected by
sequenced HMAC. The HMAC secret key is stored in the CM. There is no sensitive data
which is stored in R.Signer’s record. Hence the confidentiality requirement is not
applicable. The confidentiality requirement is considered fulfilled.
R.TSF_DATA: is the set of TOE configuration data used to operate the TOE. It shall be
protected in integrity.
Application Note 12 (Application Note 12 from [5], refined by the ST Author)
The TOE configuration data includes but not limited to: -
 CM configuration;
 HMAC key to protect the integrity of the records stored in database; and
 TLS certificate configured to allowed secure access to privileged users.
R.Privileged_User: is a TOE subject containing the set of data that uniquely identifies a
Privileged User within the TOE. It shall be protected in integrity.
R.Reference_Privileged_User_Authentication_Data: is the set of data used by the TOE to
authenticate the Privileged User. It shall be protected in integrity and confidentiality. In
case of ADSS Server SAM this is a TLS client certificate.
Application Note 13 (Application Note 13 from [5], refined by the ST Author)
The integrity of the records stored in Ascertia ADSS Server SAM database is protected by
sequenced HMAC. The HMAC secret key is stored in the CM. There is no sensitive data
which is stored in Privileged User’s record. Hence, the confidentiality requirement is not
applicable. The confidentiality requirement is considered fulfilled.
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R.Random: is random secrets, e.g. keys, used by the TOE to operate and communicate
with external parties. It shall be protected in integrity and confidentiality.
3.2Subjects
This following list of subjects interact with the TOE: -
 Signer: is the natural or legal person who uses the TOE through the SAP where they
provide the SAD and can sign DTBS/R(s) using their signing key in the CM. They are
able to perform signing operations (authorising their signing keys in the CM,
transmitting the required data, including the unique user ID, two different
authentication factors, the key ID, the key Authorisation Data and DTBS/R(s))
 Privileged User: which performs the administrative functions of the TOE and is able
to provide a DTBS/R(s) to the TOE as part of the signature operation. There are two
types of Privileged Users in Ascertia ADSS Server SAM: -
o Operators: They access the Ascertia ADSS Server SAM Admin Console to
perform different TOE specific operations, e.g. configure a CM, HMAC Key,
etc. The Operators are defined in Ascertia ADSS Server SAM Admin Console
and each operator is identified by an “Operator ID”.
o Business Applications: They access the TOE via API provided by the ADSS
RAS service to perform different TOE specific operations. On one hand, they
manage Signers (User Module) and the other, act as Signature Creation
Application (SCA). It’s important to note Business Applications do not
directly interact with the TOE instead their requests must be channelled
through the ADSS RAS Service. The TOE will only accept API request which
originate from the ADSS RAS Service. From the perspective of the TOE the
ADSS RAS Service is the Business Application.
Application Note 14 (Application Note 14 from [5], refined by the ST Author)
The list of subjects described in EN 419 241-1 [6] clause 6.2.1.2 SRG M.1.2 contains more
roles as it covers the whole T4WS. The ST writer described the specific roles it implements
and how these relate to authorisation rules in the SFRs. The TW4S maintains outside of
the TOE the following roles: -
 Privileged Roles: -
o Security Officers: have overall responsibility for administering the
implementation of the security policies, practices and have access to
security related information.
o System Auditors: authorized to view archives and audit logs of the TW4S
for the purposes of auditing the operations of the system in line with
security policy.
 Non-Privileged Roles: -
o Registration Authority (RA): authorized to send the public key certificate
to the TW4S in response of a certificate signing request.
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Application Note 15 (Application Note 15 from [5], refined by the ST Author)
The ADSS RAS Service (acts in the role of the Server Signing Application or SSA) plays a
special role as it interacts directly with the TOE. Privileged Users can interact with the
TOE directly or via the SSA. If the SSA as a service can perform administrative functions,
e.g. creating a Signer, this is in this ST considered as a Privileged User. Operators interact
directly with the TOE. Business Applications as Privileged Users interact with the TOE via
ADSS RAS Service (SSA).
Application Note 16 (Application Note 16 from [5], refined by the ST Author)
The creation of Signers, management of reference signer authentication data and signing
key generation is configured to be carried out together with a RA providing a registration
service using the SSA, as specified in e.g. ETSI EN 319 411-1 [11].
3.3Threats
The following threats are defined for the TOE. An attacker described in each of the threats
is a subject that is not authorised for the relevant operation, but may present himself as
an unknown user or as one of the other defined subjects.
3.3.1 Enrolment
The threats during enrolment are: -
T.ENROLMENT_SIGNER_IMPERSONATION
An attacker impersonates Signer during enrolment. As examples, it could be: -
 Transferring wrong R.Signer to TOE from RA; or
 Transferring wrong R.Reference_Signer_Authentication_Data to TOE from RA.
The assets R.Signer and R.Reference_Signer_Authentication_Data are threatened.
Such impersonation may allow a potential incorrect Signer authentication leading to
unauthorised signature operation on behalf of the Signer.
T.ENROLMENT_SIGNER_AUTHENTICATION_DATA_DISCLOSED
An attacker is able to obtain whole or part of R.Reference_Signer_Authentication_Data
during enrolment. This can be during generation, storage or transfer to the TOE or transfer
between the Signer and TOE. As examples, it could be: -
 by reading the data
 by changing the data, e.g. to a known value
The asset R.Reference_Signer_Authentication_Data is threatened.
Such data disclosure may allow a potential incorrect Signer authentication leading to
unauthorised signature operation on behalf of the Signer.
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The threats on enrolment are threats on the environment in case external authentication
is supported by the TOE.
T.SVD_FORGERY
An attacker modifies the R.SVD during transmission to the RA or Certification Authority.
This results in loss of R.SVD integrity in the binding of R.SVD to the signing key and to
R.Signer.
The asset R.SVD is threatened.
If the CA relies on the generation of the key pair controlled by the TOE as specified in ETSI
EN 319 411-1 [11] clause 6.3.3 d) then an attacker can forge signatures masquerading as
the R.Signer.
Application Note 17 (Application Note 17 from [5], refined by the ST Author)
The keys use by the TOE are generated in the CM. According to the Application Note 17
from [5], if this is the case, this threat can be countered without any specific measures
within the TOE. Applied. The remote signing key pair generated in CM and a Certificate
Signing Request (CSR) is produced by the CM and delivered to the TOE for transmission to
the TSP. The TOE passes it to the ADSS RAS Service (SSA) for transmission to the CA (TSP).
It receives a certificate against it from an issuing CA. The CSR is self-signed with remote
signing private key so the signature on CSR automatically serves as the Proof of Possession
of private key. This threat can be countered without any specific measure within the TOE.
3.3.2 Signer Management
T.ADMIN_IMPERSONATION
Attacker impersonates a Privileged User and updates
R.Reference_Signer_Authentication_Data, R.Signing_Key_Id or R.SVD.
The assets R.Reference_Signer_Authentication_Data, R.SVD and R.Signing_Key_Id are
threatened.
Such data modification may allow a potential incorrect Signer authentication leading to
unauthorised signature operation on behalf of the Signer.
T.MAINTENANCE_AUTHENTICATION_DISCLOSE
Attacker discloses or changes (e. g. to a known value)
R.Reference_Signer_Authentication_Data during update and is able to create a signature.
The assets R.Reference_Signer_Authentication_Data and R.Signing_Key_Id are
threatened.
Such data disclosure may allow a potential incorrect Signer authentication leading to
unauthorised signature operation on behalf of Signer.
3.3.3 Usage
This section describes threats for signature operation including authentication.
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T.AUTHENTICATION_SIGNER_IMPERSONATION
An attacker impersonates the Signer using forged
R.Reference_Signer_Authentication_Data and transmits it to the TOE during SAP and uses
it to sign the same or modified DTBS/R.
The assets R.Reference_Signer_Authentication_Data, R.SAD and R.Signing_Key_Id are
threatened.
T.SIGNER_AUTHENTICATION_DATA_MODIFIED
An attacker is able to modify R.Reference_Signer_Authentication_Data inside the TOE or
during maintenance.
The asset R.Reference_Signer_Authentification_Data is threatened.
Such data modification may allow a potential incorrect Signer authentication leading to
unauthorised signature operation on behalf of the Signer.
T.SAP_BYPASS
An attacker bypasses one or more steps in the SAP and is able to create a signature without
the Signer having authorised the operation.
The asset R.SAD is threatened.
T.SAP_REPLAY
An attacker replays one or more steps of SAP and is able to create a signature without the
Signer having authorised the operation.
The asset R.SAD is threatened.
T.SAD_FORGERY
An attacker forges or manipulates R.SAD during transfer in SAP and is able to create a
signature without the Signer having authorised the operation.
The asset R.SAD is threatened.
T.SIGNATURE_REQUEST_DISCLOSURE
An attacker obtains knowledge of R.DTBS/R or R.SAD during transfer to TOE.
The assets R.DTBS/R and R.SAD are threatened.
If the R.DTBS/R or R.SAD do not require encrypted data then this threat is mitigated.
Application Note 18 (from ST author)
This threat is mitigated. See Application Note 3 and 4.
T.DTBSR_FORGERY
An attacker modifies R.DTBS/R during transfer to TOE and is able to create a signature on
this modified R.DTBS/R without the Signer having authorised the operation on this
R.DTBS/R.
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The assets R.DTBS/R and R.SAD are threatened.
T.SIGNATURE_FORGERY
An attacker modifies R.Signature during or after creation or during transfer outside the
TOE.
The asset R.Signature is threatened.
Application Note 19 (Application Note 18 from [5])
The modification of a signature can be detected by the SSA or any relying party by
validation of the signature.
3.3.4 System
T.PRIVILEGED_USER_INSERTION
An attacker is able to create R.Privileged_User including
R.Reference_Privileged_User_Authentication_Data and is able to log on to the TOE as a
Privileged User.
The assets R.Privileged_User and R.Reference_Privileged_User_Authentication_Data are
threatened.
T.REFERENCE_PRIVILEGED_USER_AUTHENTICATION_DATA_MODIFICATION
An attacker modifies R.Reference_Privileged_User_Authentication_Data and is able to log
on to the TOE as the Privileged User.
The asset R.Reference_Privileged_User_Authentication_Data is threatened.
T.AUTHORISATION_DATA_UPDATE
Attacker impersonates Privileged User and updates R.Authorisation_Data and may be able
to activate a signing key.
The assets R.Authorisation_Data and R.Signing_Key_Id are threatened.
Application Note 20 (Application Note 19 from [5], refined by ST Author)
Applied. The TOE holds an authorisation key pair which acts as the R.Authorisation_Data.
To ensure the confidentiality, the authorisation private key is stored in encrypted form in
the Ascertia ADSS Server SAM database. HMAC ensures the integrity of the database
records.
T. AUTHORISATION_DATA _DISCLOSE
Attacker discloses R.Authorisation_Data during update and is able to activate a signing
key.
The assets R.Authorisation_Data and R.Signing_Key_Id are threatened.
T.CONTEXT_ALTERATION
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An attacker modifies system configuration R.TSF_DATA to perform an unauthorised
operation.
The assets R.Signing_Key_Id, R.SVD, R.SAD, R.Reference_Signer_Authentication_Data and
R.TSF_DATA are threatened.
T.AUDIT_ALTERATION
An attacker modifies system audit and is able hide trace of TOE modification or usage.
The assets R.SVD, R.SAD, R.Signer, R.Reference_Signer_Authentication_Data, R.DTBS/R,
R.Signature, R.AUDIT and R.TSF_DATA are threatened.
T.RANDOM
An attacker is able to guess system secrets R.RANDOM and able to create or modify TOE
objects or participate in communication with external systems.
The asset R.Random is threatened.
3.4Relation Between Threats & Assets
This following table provides an overview of the relationships between asset, associated
security properties and threats. For details consult the individual threats in the previous
sections. (The table does not contain information where the confidentiality requirement
is considered fulfilled)
Asset Security Dimensions Threats
R.Signing_Key_Id Integrity
T.ADMIN_IMPERSONATION
T.MAINTENANCE_AUTHENTICATION_DISCLOSE
T.AUTHENTICATION_SIGNER_IMPERSONATION
T.CONTEXT_ALTERATION
T.AUTHORISATION_DATA_UPDATE
T.AUTHORISATION_DATA_DISCLOSE
R.Authorisation_Data
Integrity T.AUTHORISATION_DATA_UPDATE
Confidentiality
T.AUTHORISATION_DATA_UPDATE
T. AUTHORISATION_DATA _DISCLOSE
R.SVD Integrity
T.SVD_FORGERY
T.ADMIN_IMPERSONATION
T.CONTEXT_ALTERATION
T.AUDIT_ALTERATION
R.DTBS/R
Integrity
T.SIGNATURE_REQUEST_DISCLOSURE
T.DTBSR_FORGERY
T.AUDIT_ALTERATION
Origin authentication T.DTBSR_FORGERY
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Asset Security Dimensions Threats
R.SAD
Integrity
T.AUTHENTICATION_SIGNER_IMPERSONATION
T.CONTEXT_ALTERATION
T.AUDIT_ALTERATION
T.SAP_BYPASS
T.SAP_REPLAY
T.SAD_FORGERY
Confidentiality
T.AUTHENTICATION_SIGNER_IMPERSONATION
T.SIGNATURE_REQUEST_DISCLOSURE
T.DTBSR_FORGERY
T.CONTEXT_ALTERATION
R.Signature Integrity
T.SIGNATURE_FORGERY
T.AUDIT_ALTERATION
R.Audit Integrity T.AUDIT_ALTERATION
R.Signer Integrity
T.ENROLMENT_SIGNER_IMPERSONATION
T.AUDIT_ALTERATION
R.Reference_Signer_A
uthentication_Data
Integrity
T.ENROLMENT_SIGNER_IMPERSONATION
T.ENROLMENT_SIGNER_AUTHENTICATION_DATA_
DISCLOSED
T. SIGNER_AUTEHNTICATION_DATA_MODIFIED
T.ADMIN_IMPERSONATION
T.MAINTENANCE_AUTHENTICATION_DISCLOSE
T.AUTHENTICATION_SIGNER_IMPERSONATION
T.CONTEXT_ALTERATION
T.AUDIT_ALTERATION
R.Privileged_User Integrity
T.PRIVILEGED_USER_INSERTION
T.REFERENCE_PRIVILEGED_USER_AUTHENTICATIO
N_DATA_MODIFICATION
R.Reference_Privilege
d_User_Authenticatio
n_Data
Integrity
T.PRIVILEGED_USER_INSERTION
T.REFERENCE_PRIVILEGED_USER_AUTHENTICATIO
N_DATA_MODIFICATION
R.RANDOM
Integrity T.RANDOM
Confidentiality T.RANDOM
R.TSF_DATA Integrity
T.CONTEXT_ALTERATION
T.AUDIT_ALTERATION
Table 3-1 Overview of the relationship between asset, associated security properties
and threats
3.5Organisational Security Policies
TOE shall comply with the following Organizational Security Policies (OSP) as security rules,
procedures, practices, or guidelines imposed by an organization upon its operations.
OSP.RANDOM
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The TOE is required to generate random numbers that meet a specified quality metric.
These random numbers shall be suitable for use as keys, authentication/authorisation
data, or seed data for another random number generator that is used for these purposes.
OSP.CRYPTO
The TOE shall only use algorithm, algorithm parameters and key lengths endorsed by
recognized authorities as appropriate by TSPs. This includes generation of random
numbers, signing key pairs and signatures as well as the integrity and confidentiality of
TOE assets.
Application Note 21 (Application Note 20 from [5])
For cryptographic algorithms within the European Union this is as indicated in eIDAS [8]
and an exemplary list of algorithms and parameters is given in ETSI TS 119 312 [9] or SOG-
IS [10].
3.6Assumptions
A.CERTIFICATION_AUTHORITY
It is assumed that the certificate for the R.SVD contains the R.SVD.
Application Note 22 (from ST author):
This assumption is not in the 419241-2:2017 PP [5]. Added this because the
OE.CERTIFICATE_VERIFICATION from the 419241-2:2017 [5] has a useful purpose now.
A.PRIVILEGED_USER
It is assumed that all personnel administering the TOE are trusted, competent and
possesses the resources and skills required for his tasks and is trained to conduct the
activities he is responsible for.
A.SIGNER_ENROLMENT
The Signer shall be enrolled and certificates managed in conformance with the regulations
given in eIDAS [8]. Guidance for how to implement an enrolment and certificate
management system in conformance with [8] are given in e.g. EN 319 411-1[11] or for
qualified certificate in e.g. EN 319 411-2 [12].
A.SIGNER_AUTHENTICATION_DATA_PROTECTION
It is assumed that the Signer will not disclose his authentication factors.
A.SIGNER_DEVICE
It is assumed that the device and SIC used by Signer to interact with the SSA and the TOE
is under the Signer’s control for the signature operation, i.e. protected against malicious
code.
A.CA
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It is assumed that the qualified TSP that issues Signer qualified certificates is compliant
with the relevant requirements for qualified TSP's as defined in eIDAS [8].
A.ACCESS_PROTECTED
It is assumed that the TOE operates in a protected environment that limits physical access
to the TOE to authorised Privileged Users. The TOE software and hardware environment
(including client applications) is installed and maintained by Privileged Users in a secure
state that mitigates against the specific risks applicable to the deployment environment.
It is assumed that any audit generated by the TOE are only handled by authorised personal
in a physical secured environment. The personal that carries these activities should act
under established practices.
It is assumed that where copies of data protected by the TOE are managed outside of the
TOE, client applications and other entities must provide appropriate protection for that
data to a level required by the application context and the risks in the deployment
environment.
Application Note 23 (Application Note 21 from [5], refined by ST author)
All the data are stored outside the TOE but managed by the TOE. The HSM is secure since
it is certified according to EN 419 221-5 [7]. Data stored in the database are secured with
HMAC key which is also generated and kept in the HSM.
A.AUTH_DATA
It is assumed that the SAP is designed in such a way that the activation of the signing key
is under sole control of the Signer with a high level of confidence. If SAD is received by the
TOE, it must be assumed that the SAD was submitted under the full control of the Signer
by means that are in possession of the Signer.
A.TSP_AUDITED
It is assumed that the TSP deploying the SSA and TOE is a qualified TSP according to article
3 (20) of eIDAS Regulation (EU) No 910/2014 [8] and audited to be compliant with the
requirements for TSP's given by eIDAS [8].
A.SEC_REQ
It is assumed that the TSP establishes an operating environment according to the security
requirements for SCAL2 defined in EN 419 241-1 [11].
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4. Security Objectives
This section identifies and defines the security objectives for the TOE and its operational
environment. These security objectives reflect the stated intent, counter the identified
threats, and take into account the assumptions.
4.1Security objectives for the TOE
The following security objectives describe security functions to be provided by the TOE.
4.1.1 Enrolment
OT.SIGNER_PROTECTION
The TOE shall ensure that data associated to R.Signer is protected in integrity and if needed
in confidentiality.
OT.REFERENCE_SIGNER_AUTHENTICATION_DATA
The TOE shall be able to securely handle signer authentication data, R.Reference_Signer_
Authentication_Data, as part of R.Signer.
OT.SIGNER_KEY_PAIR_GENERATION
The TOE shall be able to securely use the CM to generate R.Signer signing key pairs and
assign R.Signing_Key_Id and R.SVD to R.Signer.
OT.SVD
The TOE shall ensure that the R.SVD linked to R.Signer is not modified before it is certified.
4.1.2 User Management
OT.PRIVILEGED_USER_MANAGEMENT
The TOE shall ensure that any modification to R.Privileged_User and
R.Reference_Privileged_User_Authentication_Data are performed under control of a
Privileged User.
OT.PRIVILEGED_USER_AUTHENTICATION
The TOE shall ensure that an administrator with a Privileged User is authenticated before
any action on the TOE is performed.
Application Note 24 (Application Note 22 from [5])
The exception to this objective is when the initial (set of) Privileged Users are created as
part of system initialisation.
OT.PRIVILEGED_USER_PROTECTION
The TOE shall ensure that data associated to R.Privileged_User are protected integrity and
if needed in confidentiality.
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OT.SIGNER_MANAGEMENT
The TOE shall ensure that any modification to R.Signer,
R.Reference_Signer_Authentication_Data, R.Signing_Key_Id and R.SVD are performed
under control of the Signer or Privileged User.
4.1.3 Usage
OT.SAD_VERIFICATION
The TOE shall verify the SAD. That is, it shall check there is a link between the SAD elements
and ensure the Signer is strongly authenticated.
Application Note 25 (Application Note 23 from [5], refined by the ST Author)
In this case, the TOE derives authorisation data from authentication data in the SAD and
uses this to authorise the signing key in the CM. This function does not depend on the
controls provided by the CM.
Application Note 26 (Application Note 24 from [5])
Requirements for authentication are described in EN 419 241-1 [11] SRA_SAP.1.1.
OT.SAP
The TOE shall implement the server-side endpoint of a SAP, which provides the following:
-
 Signer authentication;
 Integrity of the transmitted SAD;
 Confidentiality of at least the elements of the SAD which contains sensitive
information; and
 Protection against replay, bypass of one or more steps and forgery.
Application Note 27 (Application Note 25 from [5], refined by the ST Author)
The Signer authentication is assumed to be conducted according to EN 419 241-1 [6]
SCAL.2 for qualified signatures. This means Signer authentication can be carried out in the
following way: -
 In the case of the current TOE it is done directly by the SAM.
OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION
The TOE shall ensure signature authentication data is protected against attacks when
transmitted to the TOE which would compromise its use for authentication.
OT.DTBSR_INTEGRITY
The TOE shall ensure that the R.DTBS/R is protected in integrity when transmitted to the
TOE.
OT.SIGNATURE_INTEGRITY
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The TOE shall ensure that a signature can’t be modified inside the TOE.
OT.CRYPTO
The TOE shall only use algorithm, algorithm parameters and key lengths endorsed by
recognized authorities. This includes generation of random numbers, signing key pairs
and signatures as well as the integrity and confidentiality of TOE assets.
4.1.4 System
OT.RANDOM
Random numbers generated used by the TOE for use as keys, in protocols or seed data for
another random number generator that is used for these purposes shall meet a defined
quality metric in order to ensure that random numbers are not predictable and have
sufficient entropy.
OT.SYSTEM_PROTECTION
The TOE shall ensure that modification of R.TSF_DATA is authorised by Privileged User and
that unauthorised modification can be detected.
OT.AUDIT_PROTECTION
The TOE shall ensure that modifications to R.AUDIT can be detected.
4.2Security Objectives for the Operational Environment
OE.SVD_AUTHENTICITY
The operational environment shall ensure the SVD integrity during transmission outside
the TOE to the CA.
OE.CA_REQUEST_CERTIFICATE
The operational environment shall ensure that the qualified TSP that issues qualified
certificates is compliant with the relevant requirements for qualified TSP’s as defined in
eIDAS [8].
The operational environment shall use a process for requesting a certificate, including SVD
and Signer information, and CA signature in a way, which demonstrates the Signer is in
control of the signing key associated with the SVD presented for certification. The integrity
of the request shall be protected.
OE.CERTIFICATE_VERFICATION
The operational environment shall verify that the certificate for the R.SVD contains the
R.SVD.
OE.SIGNER_AUTHENTICATION_DATA
The Signer’s management of authentication factors data outside the TOE shall be carried
out in a secure manner.
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OE.DELEGATED_AUTHENTICATION
If the TOE has support for and is configured to use delegated authentication then the TSP
deploying the SSA and TOE shall ensure that all requirements in EN 419 241-1 [11]
SRA_SAP.1.1 are met.
In addition, the TSP shall ensure that: -
 The delegated party fulfils all the relevant requirements of this standard and the
requirements for registration according to the eIDAS Regulation (EU) No 910/2014
[8]; or
 The authentication process delegated to the external party uses an electronic
identification means issued under a notified scheme that is included in the list
published by the Commission pursuant to Article 9 of the eIDAS Regulation (EU) No
910/2014 [8].
If the Signer is only authenticated using a delegated party, the TSP shall ensure that the
secret key material used to authenticate the delegated party to the TOE shall reside in a
certified CM consistent with the requirement as defined in EN 419 241-1 [11] SRG_KM.1.1.
OE.DEVICE
The device, computer/tablet/smart phone containing the SIC and which is used by the
Signer to interact with the TOE shall be protected against malicious code. It shall
participate using SIC as local part of the SAP and may calculate SAD as described in EN 419
241-1 [11]. It may be used to view the document to be signed.
OE.ENV
The TSP deploying the SSA and TOE shall be a qualified TSP according to article 3 (20) of
eIDAS Regulation (EU) No 910/2014 [8] and audited to be compliant with the requirements
for TSP's given by eIDAS [8]. The audit of the qualified TSP shall cover the security
objectives for the operational environment specified in this clause.
The TOE shall operate in a protected environment that limits physical access to the TOE
to authorised privileged users. The TOE software and hardware environment (including
client applications) shall be installed and maintained by Privileged Users in a secure state
that mitigates against the specific risks applicable to the deployment environment,
including (where applicable): -
 Protection against loss or theft of the TOE or any of its externally stored assets.
 Inspections to deter and detect tampering (including attempts to access side-
channels, or to access connections between physically separate parts of the TOE,
or parts of the hardware appliance).
 Protection against the possibility of attacks based on emanations from the TOE,
e.g. electromagnetic emanations, according to risks assessed for the operating
environment.
 Protection against unauthorised software and configuration changes on the TOE
and the hardware appliance.
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 Protection to an equivalent level of all instances of the TOE holding the same
assets, e.g. where a key is present as a backup in more than one instance of the
TOE.
OE.CRYPTOMODULE_CERTIFIED
The TOE is implemented as a local application within the same physical boundary as the
CM defined in EN 419221-5 [7] and relies on said CM for providing a tamper-protected
environment and for cryptographic functionality and random number generation.
Application Note 28 (Application Note 26 from [5], refined by ST author)
Applied.
OE.TW4S_CONFORMANT
The TOE shall be operated by a qualified TSP in an operating environment conformant with
EN 419241-1 [6].
4.2.1 Security Problem Definition & Security Objectives
The following tables map security objectives with the security problem definition.
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Enrolment
OT.SIGNER_PROTECTION
OT.REFERENCE_SIGNER_AUTHE
NTICATION_DATA
OT.SIGNER_KEY_PAIR_GENERATION
OT.SVD
Enrolment
T.ENROLMENT_SIGNER_IMPERSONATION X X
T.ENROLMENT_SIGNER_AUTHENTICATION_DATA_DISCLOSED X X
T.SVD_FORGERY X X
Signer Management
T.ADMIN_IMPERSONATION
T.MAINTENANCE_AUTHENTICATION_DISCLOSE X
Usage
T.AUTHENTICATION_SIGNER_IMPERSONATION
T.SIGNER_AUTHENTICATION_DATA_MODIFIED X
T.SAP_BYPASS
T.SAP_REPLAY
T.SAD_FORGERY
T.SIGNATURE_REQUEST_DISCLOSURE
T.DTBSR_FORGERY
T.SIGNATURE_FORGERY
System
T.PRIVILEGED_USER_INSERTION
T.REFERENCE_PRIVILEGED_USER_AUTHENTICATION_DATA_MODIFICATION
T.AUTHORISATION_DATA_UPDATE
T.AUTHORISATION_DATA_DISCLOSE
T.CONTEXT_ALTERATION
T.AUDIT_ALTERATION
T.RANDOM
Table 4-1 TOE Security objectives (Enrolment) and threats
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User
Management
OT.PRIVILEGED_USER_MANAGEMENT
OT.PRIVILEGED_USER_AUTHENTICATION
OT.PRIVILEGED_USER_PROTECTION
OT.SIGNER_MANAGEMENT
System
OT.RANDOM
OT.SYSTEM_PROTECTION
OT.AUDIT_PROTECTION
Enrolment
T.ENROLMENT_SIGNER_IMPERSONATION X
T.ENROLMENT_SIGNER_AUTHENTICATION_DATA_DISCL
OSED
T.SVD_FORGERY
Signer Management
T.ADMIN_IMPERSONATION X X
T.MAINTENANCE_AUTHENTICATION_DISCLOSE
Usage
T.AUTHENTICATION_SIGNER_IMPERSONATION
T.SIGNER_AUTHENTICATION_DATA_MODIFIED
T.SAP_BYPASS
T.SAP_REPLAY
T.SAD_FORGERY
T.SIGNATURE_REQUEST_DISCLOSURE
T.DTBSR_FORGERY
T.SIGNATURE_FORGERY
System
T.PRIVILEGED_USER_INSERTION X X
T.REFERENCE_PRIVILEGED_USER_AUTHENTICATION_DA
TA_MODIFICATION
X X X
T.AUTHORISATION_DATA_UPDATE X
T.AUTHORISATION_DATA_DISCLOSE X
T.CONTEXT_ALTERATION X
T.AUDIT_ALTERATION X
T.RANDOM X
Table 4-2 TOE Security objectives (Signer Management and System) and threats
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Usage
OT.SAD_VERIFICATION
OT.SAP
OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION
OT.DTBSR_INTEGRITY
OT.SIGNATURE_INTEGRITY
OT.CRYPTO
Enrolment
T.ENROLMENT_SIGNER_IMPERSONATION
T.ENROLMENT_SIGNER_AUTHENTICATION_DATA_DISCLOSED
T.SVD_FORGERY X
Signer Management
T.ADMIN_IMPERSONATION
T.MAINTENANCE_AUTHENTICATION_DISCLOSE
Usage
T.AUTHENTICATION_SIGNER_IMPERSONATION X
T.SIGNER_AUTHENTICATION_DATA_MODIFIED X X
T.SAP_BYPASS X
T.SAP_REPLAY X
T.SAD_FORGERY X X
T.SIGNATURE_REQUEST_DISCLOSURE X
T.DTBSR_FORGERY X
T.SIGNATURE_FORGERY X X
System
T.PRIVILEGED_USER_INSERTION
T.REFERENCE_PRIVILEGED_USER_AUTHENTICATION_DAT
A_MODIFICATION
T.AUTHORISATION_DATA_UPDATE
T.AUTHORISATION_DATA_DISCLOSE
T.CONTEXT_ALTERATION
T.AUDIT_ALTERATION
T.RANDOM
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Table 4-3 TOE Security objectives (Usage) and threats
OT.SIGNER_PROTECTION
OT.REFERENCE_SIGNER_AUTHENTICATION_DATA
OT.SIGNER_KEY_PAIR_GENERATION
OT.SVD
OT.RANDOM
OT.CRYPTO
OSP.RANDOM X
OSP.CRYPTO X
Table 4-4 TOE Security Objectives and Organizational Security Policies
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OE.SVD_AUTHENTICITY
OE.CA_REQUEST_CERTIFICATE
OE.CERTIFICATE_VERIFICATION
OE.SIGNER_AUTHENTICATION_DATA
OE.DELEGATED_AUTHENTICATION
1
OE.DEVICE
OE.ENV
OE.CRYPTOMODULE_CERTIFIED
OE.TW4S_CONFORMANT
Enrolment
T.ENROLMENT_SIGNER_IMPERSONATION X
T.ENROLMENT_SIGNER_AUTHENTICATION_DATA_DIS
CLOSED
X X
T.SVD_FORGERY X X
Signer Management
T.ADMIN_IMPERSONATION
T.MAINTENANCE_AUTHENTICATION_DISCLOSE
Usage
T.AUTHENTICATION_SIGNER_IMPERSONATION
T.SIGNER_AUTHENTICATION_DATA_MODIFIED
T.SAP_BYPASS X
T.SAP_REPLAY X
T.SAD_FORGERY X X
T.SIGNATURE_REQUEST_DISCLOSURE
T.DTBSR_FORGERY X
T.SIGNATURE_FORGERY
System
T.PRIVILEGED_USER_INSERTION
T.REFERENCE_PRIVILEGED_USER_AUTHENTICATION_
DATA_MODIFICATION
T.AUTHORISATION_DATA_UPDATE
T.AUTHORISATION_DATA_DISCLOSE
T.CONTEXT_ALTERATION
T.AUDIT_ALTERATION
T.RANDOM
Table 4-5 Threats and Security Objectives for the environment
1 No delegated party is involved, only the SAM verifies the Signer’s authentication factor(s). The TOE
does not use delegated authentication. Because of this, this OE is not tracing to any security problem.
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OE.SVD_AUTHENTICITY
OE.CA_REQUEST_CERTIFICATE
OE.CERTIFICATE_VERIFICATION
OE.SIGNER_AUTHENTICATION_DATA
OE.DELEGATED_AUTHENTICATION
2
OE.DEVICE
OE.ENV
OE.CRYPTOMODULE_CERTIFIED
OE.TW4S_CONFORMANT
Organisational Security Policies
OSP.RANDOM
OSP.CRYPTO X
Assumptions
A.PRIVILEGED_USER X
A.SIGNER_ENROLMENT X
A.SIGNER_AUTHENTICATION_DATA_PROTECTI
ON
X
A.SIGNER_DEVICE X
A.CA X
A.ACCESS_PROTECTED X
A.AUTH_DATA X
A.TSP_AUDITED X
A.SEC_REQ X
A.CERTIFICATION_AUTHORITY X
Table 4-6 Organizational Security Policies and Security Objectives for the environment
and Assumptions and Security Objectives for the environment
4.2.2 Rationale for the Security Objectives
This section provides a rationale objective that covers each threat, organizational security
policy and assumption. Except the OE. DELEGATED_AUTHENTICATION, because the TOE
does not use delegated authentication. Because of this, this OE is not tracing to any security
problem.
4.2.2.1 Threats & Objectives
T.ENROLMENT_SIGNER_IMPERSONATION is covered by OT.SIGNER_PROTECTION requiring
R.Signer to be protected in integrity and for sensitive parts in confidentiality.
It is also covered by OT.SIGNER_MANAGEMENT requiring the R.Signer to be securely created.
It is also covered by OT.REFERENCE_SIGNER_AUTHENTICATION_DATA requiring the TOE to be
2 No delegated party is involved, only the SAM verifies the Signer’s authentication factor(s). The TOE
does not use delegated authentication. Because of this, this OE is not tracing to any security problem.
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able to assign Signer authentication data to the R.Signer.
It is also covered by OE.TW4S_CONFORMANT as that requires signer enrolment to be handled
in accordance with [14] for level at least substantial.
T.ENROLMENT_SIGNER_AUTHENTICATION_DATA_DISCLOSED is covered by
OT.REFERENCE_SIGNER_AUTHENTICATION_DATA requiring that authentication data be
securely handled.
It is also covered by OT.SIGNER_PROTECTION requiring that the attributes, including Signer
authentication data, be protected in integrity and if needed in confidentiality.
It is also covered by OE.SIGNER_AUTHENTICATION_DATA requiring the Signer to keep his
authentication data secret.
It is also covered by OE.DEVICE requiring the device used by the Signer not to disclose
authentication data.
T.SVD_FORGERY is covered by OT.SIGNER_KEY_PAIR_GENERATION requiring a CM to
generate R.Signer key pair.
It is also covered by OT.SVD requiring the SVD to be protected while inside the TOE.
It is also covered by OT.CRYPTO requiring the usage of endorsed algorithms.
It is also covered by OE.SVD_AUTHENTICITY requiring the environment to protect the SVD
during transmit from the TOE to the CA.
It is also covered by OE.CA_REQUEST_CERTIFICATE requiring the certification request to be
protected in integrity.
T.ADMIN_IMPERSONATION is covered by OT.SIGNER_MANAGEMENT and
OT.PRIVILEGED_USER_AUTHENTICATION requiring any changes to the Signer representation
and attributes are carried out in an authorised manner.
T.MAINTENANCE_AUTHENTICATION_DISCLOSE is covered by
OT.REFERENCE_SIGNER_AUTHENTICATION_DATA requiring that authentication data be
securely handled.
T.AUTHENTICATION_SIGNER_IMPERSONATION is covered by OT.SAD_VERIFICATION
requiring that the TOE checks the SAD received in the SAP.
T.SIGNER_AUTHENTICATION_DATA_MODIFIED is covered by
OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION requiring the SAD transported
protected in the SAP.
It is also covered by OT.REFERENCE_SIGNER_AUTHENTICATION_DATA requiring that
authentication data be securely handled.
It is also covered by OT.SAP requiring the integrity of the SAD is protected during transmit in
the SAP.
T.SAP_BYPASS is covered by OT.SAP requiring that all steps, including SAD verification, of the
SAP must completed.
It is also covered by OE.DEVICE requiring the SIC to participate in the SAP.
T.SAP_REPLAY is covered by OT.SAP requiring that the SAP must be able to resist whole or
part of it being replayed.
It is also covered by OE.DEVICE requiring the SIC to participate the in SAP.
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T.SIGNATURE_REQUEST_DISCLOSURE is covered by the OT.SAP requiring the protocol to be
able to transmit data securely.
T.DTBSR_FORGERY is covered by OT.DTBSR_INTEGRITY requiring the R.DTBS/R to be
protected in integrity during transmit to the TOE.
It is also covered by OE.DEVICE requiring the SIC to participate in the SAP.
T.SIGNATURE_FORGERY is covered by OT.SIGNATURE_INTEGRITY requiring that the signature
is protected in integrity inside the TOE.
It is also covered by OT.CRYPTO requiring the usage of endorsed algorithms.
T.PRIVILEGED_USER_INSERTION is covered by OT.PRIVILEGED_USER_MANAGEMENT
requiring only Privileged User can create new R.Privileged_User and
OT.PRIVILEGED_USER_AUTHENTICATION that requires a Privileged User to be authenticated.
T.REFERENCE_PRIVILEGED_USER_AUTHENTICATION_DATA_MODIFICATION is covered by
OT.PRIVILEGED_USER_MANAGEMENT requiring only Privileged User can modify
R.Privileged_User and OT.PRIVILEGED_USER_AUTHENTICATION that requires a Privileged
User to be authenticated.
It is also covered by OT.PRIVILEGED_USER_PROTECTION requiring the Privileged User to be
protected in integrity.
T.AUTHORISATION_DATA_UPDATE is covered by OT.SYSTEM_PROTECTION requiring any
unauthorised modification to TOE configuration to be detectable.
T.AUTHORISATION_DATA_DISCLOSE is covered by OT.SYSTEM_PROTECTION requiring any
unauthorised modification to TOE configuration to be detectable.
T.CONTEXT_ALTERATION is covered by OT.SYSTEM_PROTECTION requiring any unauthorised
modification to TOE configuration to be detectable.
T.AUDIT_ALTERATION is covered by OT.AUDIT_PROTECTION requiring any audit modification
can be detected.
T.RANDOM is covered by OT.RANDOM requiring that random numbers are not predictable
and have sufficient entropy.
T.SAD_FORGERY is covered by OT.SAP requiring the TOE to be able to detect if the SAD has
been modified during transmit to the TOE.
It is also covered by OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION requiring
signature authentication datato be protected during transmit to the TOE.
It is also covered by OE.SIGNER_AUTHENTICATION_DATA requiring the Signer to protect their
authentication data.
It is also covered by OE.DEVICE requiring the device used by the Signer to participate correctly
in the SAP, in particular the device shall not disclose authentication data.
4.2.2.2 Organizational Security Policies & Objectives
OSP.RANDOM is covered by OT.RANDOM requiring that random numbers are not predictable
and have sufficient entropy.
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OSP.CRYPTO is covered by OT.CRYPTO requiring the usage of endorsed algorithms and
OE.CRYPTOMODULE_CERTIFIED requiring a cryptographic module to provide a tamper-
protected environment and for cryptographic functionality and random number generation.
4.2.2.3 Assumptions & Objectives
A.PRIVILEGED_USER is covered by OE.TW4S_CONFORMANT which requires that the system
where the TOE operates is compliant with EN 419 241-1 [6] where clause SRG M1.8 requires
that administrators are trained.
A.SIGNER_ENROLMENT is covered by OE.ENV requiring the TSP to be audited.
A.SIGNER_AUTHENTICATION_DATA_PROTECTION is covered by
OE.SIGNER_AUTHENTICATION_DATA requiring the Signer to protect his authentication data.
A.SIGNER_DEVICE is covered by OE.DEVICE requiring the Signer’s device to be protected
against malicious code.
A.CA is covered by OE.CA_REQUEST_CERTIFICATE requiring that the CA will issue certificates
containing the SVD.
A.ACCESS_PROTECTED is covered by OE.ENV requiring the TOE be operated in an environment
with physical access controls.
A.AUTH_DATA is covered by OE.DEVICE requiring the device to participate correctly in the
SAP.
A.TSP_AUDITED is covered by OE.ENV requiring that the TOE is operated by a qualified TSP.
A.SEC_REQ is covered by OE.TW4S_CONFORMANT requiring the system where the TOE
operates is compliant with EN 419 241-1 [6].
A.CERTIFICATION_AUTHORITY is covered by OE.CERTIFICATE_VERIFICATION.
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FCS_RNG: Generation of random numbers
5. Extended Components Definitions
5.1 Class FCS: Cryptographic Support
The Class FCS: Cryptographic Support as defined in CCPART2 [2] is extended with a new
family: Generation of Random Numbers (FCS_RNG). The family is concerned with
generation of random numbers. The following picture illustrates the decomposition of the
Class FCS: Cryptographic Support with the added family FCS_RNG:
5.1.1 Generation of Random Numbers (FCS_RNG)
This family describes the functional requirements for random number generation used for
cryptographic purposes.
Family behaviour:
This family defines quality requirements for the generation of random numbers, which are
intended to be used for cryptographic purposes.
Component levelling:
Management: FCS_RNG.1
There are no foreseen management activities.
1
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Audit: FCS_RNG.1
There are no actions defined to be auditable.
FCS_RNG.1 Generation of random numbers
Hierarchical to: No other components.
Dependencies: No dependencies.
FCS_RNG.1.1 The TSF shall provide a [selection: physical, non-physical true,
deterministic, hybrid physical, hybrid deterministic] random
number generator that implements: [assignment: list of security
capabilities].
FCS_RNG.1.2 The TSF shall provide [selection: bits, octets of bits, numbers
[assignment: format of the numbers]] that meet [assignment: a
defined quality metric].
Application Note 29 (Application Note 27 from [5])
A physical random number generator (RNG) produces the random number by a noise
source based on physical random processes. A non-physical true RNG uses a noise source
based on non-physical random processes like human interaction (key strokes, mouse
movement). A deterministic RNG uses a random seed to produce a pseudorandom output.
A hybrid RNG combines the principles of physical and deterministic RNGs where a hybrid
physical RNG produces at least the amount of entropy the RNG output may contain and
the internal state of a hybrid deterministic RNG output contains fresh entropy but less
than the output of RNG may contain.
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6. Security Requirements
6.1 Use of requirement specifications
Common Criteria allows several operations to be performed on functional requirements;
refinement, selection, assignment, and iteration. Each of these operations is used in this
ST and the underlying PP. The footnotes in this ST indicate the operations of the PP and
the ST as well.
The refinement operation is used to add detail to a requirement, and thus further restricts
a requirement. Refinement of security requirements is denoted by the word “refinement”
in bold text and/or the added/changed words are in bold text. In cases where words from
a CC requirement were deleted, a separate attachment indicates the words that were
removed. If the refinement belongs to a selection or to an assignment it is denoted as
underlined bold. In case of the selection or assignment is filled by the ST author it is
denoted double underlined bold. In case of the refinement is the PP modification it is
denoted as underlined italic bold.
The selection operation is used to select one or more options provided by the CC in stating
a requirement. Selections that have been made by the PP authors are denoted as
underlined text and the original text of the component is given by a footnote. Selections
to be filled in by the ST author appear in square brackets with an indication that a selection
is to be made, [selection:], and are italicized. Selections filled in by the ST author are
denoted as double underlined text and a foot note where the selection choices from the
PP are listed.
The assignment operation is used to assign a specific value to an unspecified parameter,
such as the length of a password. Assignments that have been made by the PP authors are
denoted by showing as underlined text and the original text of the component is given by
a footnote. Assignments to be filled in by the ST author appear in square brackets with an
indication that an assignment is to be made [assignment:], and are italicized. In some
cases, the assignment made by the PP authors defines a selection to be performed by the
ST author. Thus, this text is underlined and italicized like this. Assignments filled in by the
ST author are denoted as double underlined text.
The iteration operation is used when a component is repeated with varying operations.
Iteration is denoted by showing a slash “/”, and the iteration indicator after the
component identifier.
6.2 Subjects, Objects and Operations
This section describes the subjects, objects and operations support by the TOE.
Subject Description
R.Signer Represents within the TOE, the end user that wants to create a
digital signature
R.Privileged_User Represents within the TOE, a privileged user that can administer
the TOE and a few operations relevant for R.Signer
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Table 6-1 Subjects
Object Description
R.Reference_Privileg
ed_User_Authenticat
ion_Data
Data used by the TOE to authenticate a Privileged_User
R.Reference_Signer_
Authentication_Data
Data used by the TOE to authenticate a Signer
R.SVD The public part of a R.Signer signature key pair
R.Signing_Key_Id An identifier representing the private part of a R.Signer
signature key pair
R.DTBS/R Data to be signed representation
R.Authorisation_Data Data used by the Cryptographic Module to activate the private
part of a R.Signer signature key pair
R.Signature The result of a signature operation
R.TSF_DATA TOE Configuration Data
Table 6-2 Objects
Subject Operation Object Description
R.Privileged_User
(Operator)
Create_New_P
rivileged_User
R.Privileged_User
R.Reference_Privileg
ed_User_Authentica
tion_Data
A new privileged user
can be created which
covers the object
representing the new
privileged user as well
as the object used to
authenticate the
newly created
privileged user.
R.Privileged_User
(Business
Application)
Create_New_S
igner
R.Signer
R.Reference_Signer_
Authentication_Data
A new signer can be
created which covers
the object
representing the new
signer as well as the
object used to
authenticate the
newly created signer.
R.Privileged_User
(Business
Application)
R.Signer
Generate_Sign
er_Key_Pair
R.Signer
R.SVD
R.Signing_Key_Id
A key pair can be
generated and
assigned to a signer.
R.Privileged_User
(Business
Application,
Operator)
Signer_Key_Pa
ir_Deletion
R.Signer
R.SVD
R.Signing_Key_Id
A key pair can be
deleted from a signer.
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Subject Operation Object Description
R.Signer
R.Privileged_User
(Business
Application,
Operator)
Signer_Mainte
nance
R.Signer
R.Reference_Signer_
Authentication_Data
Maintain the signer’s
security attributes.
R.Privileged_User
(Business
Application)
Supply_DTBS/
R
R.Signer
R.DTBS/R
Data to be signed by a
signer can be supplied
by a privileged user.
R.Signer Signing R.Authorisation_Dat
a
R.Signer
R.Signing_Key_Id
R.DTBS/R
R.Signature
A signer can sign data
to be signed resulting
in a signature.
R.Privileged_User
(Operator)
TOE_Maintena
nce
R.TSF_DATA The TOE configuration
can be maintained by
a privileged user.
Table 6-3 Subject, Objects and Operations
6.3 SFRs overview
This section gives an overview of how the SFRs are related to handle TOE usage scenarios
and Signer object.
Signer object
 FIA_ATD.1 and FIA_USB.1 requires that the R.Signer object is maintained by the
TOE.
 FDP_ITC.2/Signer describes requirements for importing the R.Signer object.
 FDP_ETC.2/Signer describes requirements for exporting the R.Signer object
 FDP_UIT.1 requires the R.Signer object to be protected in integrity when imported
and exported.
 FPT_TDC.1 requires the TOE to be able to interpret R.Signer object related data
when shared with SSA.
 FMT_MSA.1, FMT_MSA.2 and FMT_MSA.3 describes rules for creation,
maintaining and usage of the R.Signer object as well as requirements to its values.
Authentication
 FIA_AFL.1/* limit the amount of authentication attempts
 FDP_UCT.1 ensure that access control and information flow data are transmitted
in a confidential way.
 FIA_UID.2 and FIA_UAU.1 requires that each user is identified and authenticated
before any action on behalf of the user can take place.
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 FIA_UAU.5/Signer and FIA_UAU.5/Privileged User describe the list of
authentication mechanism
Create Signer
 FDP_ACC.1/Signer Creation using FDP_ACF.1/Signer Creation describes access
control requirements for creating a R.Signer object.
 FIA_USB.1 defines authorisation rules for creating new R.Signer objects.
Signer Key Pair Generation
 FDP_ACC.1/Signer Key Pair Generation using FDP_ACF.1/Signer Key Pair
Generation describes access control requirements for signing key pair generation.
 FCS_CKM.1/* describe rules for how signing key pair are generated
Signer Key Pair Deletion
 FDP_ACC.1/Signer Key Pair Deletion using FDP_ACF.1/Signer Key Pair Deletion
describes access control requirements for signing key pair deletion.
 FCS_CKM.4 requires keys to be securely destructed.
Signer Maintenance
 FDP_ACC.1/Signer Maintenance using FDP_ACF.1/Signer Maintenance describes
access control requirements for updating the
R.Reference_Signer_Authentication_Data of a R.Signer object.
Supply DTBS/R
 FDP_ACC.1/Supply DTBS/R using FDP_ACF.1/Supply DTBS/R describes access
control requirements for a Privileged User to supply a DTBS/R(s).
Signing
 FDP_IFF.1/Signer and FDP_IFC.1/Signer describing requirements on preconditions
for a signature operation can be carried out.
 FDP_UIT.1 requires the R.SAD object to be protected from modification and replay.
 FDP_ACC.1/Signing using FDP_ACF.1/Signing describes access control
requirements for signing.
 FCS_COP.1/* requires the TOE to perform cryptographic operation conformant
with a ST specified list of algorithms.
 FPT_RPL.1 requires detection of replay of the R.SAD and reject signature operation
in case of replay detected.
 FPT_STM1 is responsible for reliable time stamps for the signatures.
Privileged User object
 FIA_ATD.1 and FIA_USB.1 requires that the R.Privileged User object is maintained
by the TOE.
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 FDP_ITC.2/Privileged User describes requirements for importing the R.Privileged
User object.
 FDP_ETC.2/ Privileged User describes requirements for exporting the R.Privileged
User object
 FDP_UIT.1 requires the R.Privileged User object to be protected in integrity when
imported and exported.
 FPT_TDC.1 requires the TOE to be able to interpret R.Privileged User object when
shared with a trusted IT product the SSA.
 FMT_MSA.1, FMT_MSA.2, FMT_MSA.3 describes rules for creation, maintaining
and usage of the R.Privileged User object as well as requirements to its values.
 FDP_IFC.1/Privileged user and FDP_IFF.1/Privileged User describes rules accessing
any of Privileged User’s data for Operator.
Privileged User Creation
 FDP_ACC.1/Privileged User Creation using FDP_ACF.1/ Privileged User Creation
describes access control requirements for creating a R.Privileged User object.
 FIA_USB.1 defines authorisation rules for creating new R.Privileged User objects.
TOE Maintenance
 FDP_ACC.1/TOE Maintenance using FDP_ACF.1/TOE Maintenance
 FMT_SMF.1, FMT_SMR.2 and FMT_MTD.1 requires the TOE to be able to carry out
management functions and maintain users and roles.
 FPT_PHP.1 and FPT_PHP.3 requires the detection of any physical tampering or
opening the case that compromises the TOE.
Audit
 FAU_GEN.1 and FAU_GEN.2 describes what shall be audited.
Communication
 FTP_TRP.1/SSA and FTP_TRP.1/SIC requires that either the Privileged User or the
Signer initiates the communication.
 FCS_RNG.1 is required to generate random numbers for securing communication
channels.
 FTP_ITC.1/CM requires trusted path for communication between SAM and the CM.
6.4 Security Functional Requirements
The individual security functional requirements are specified in the sections below.
6.4.1 Security Audit (FAU)
FAU_GEN.1 Audit Generation
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Hierarchical to: No other components.
Dependencies: FPT_STM.1 Reliable time stamps.
FAU_GEN.1.1 The TSF shall be able to generate an audit record of the following
auditable events: -
a) Start-up and shutdown of the audit functions;
b) All auditable events for the not specified 3 level of audit;
and
c) Privileged User management;
d) Privileged User authentication;
e) Signer management;
f) Signer authentication;
g) Signing key generation;
h) Signing key destruction;
i) Signing key activation and usage including the hash of the
DTBS/R(s) and R.Signature;
j) Change of TOE configuration;4
k) none 5
Application Note 30 (Application Note 28 from [5], refined by the ST Author).
Management of R.Privileged User and R.Signer objects include all events, which creates,
modifies or deletes the R.Signer or R.Privileged User objects.
No delegated party is involved, only the SAM verifies the Signer's authentication factor(s).
Change of TOE configuration shall include all events, which creates, modifies and deletes
the configuration object.
Application Note 31 (Application Note 29 from [5], refined by the ST Author)
Generation of a certification request is usage of the signing key and mandates an audit
trail.
Application Note 32 (Application Note 30 from [5], refined by the ST Author)
Applied.
The audit logs will contain the DTBS/R with Base64 encoding and the entire database
record will be HMAC protected (using HMACSHA256).
FAU_GEN.1.2 The TSF shall record within each audit record at least the following
information: -
3 [selection: minimum, basic, detailed, not specified]
4 [assignment: other specifically defined auditable events.]
5 [assignment: other specifically defined auditable events]
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a) Date and time of the event, type of event, subject identity
(if applicable), and the outcome (success or failure) of the
event; and
b) For each audit event type, based on the auditable event
definitions of the functional components included in the
ST:
 Type of action performed (success or failure),
 identity of the role which performs the operation,
 unique log ID,
 readable message or status about the operation. 6
Application Note 33 (Application Note 31 from [5], refined by the ST Author)
Applied.
Audit trail does not include any data which allow to retrieve sensitive data.
FAU_GEN.2 User identity association
Hierarchical to: No other components.
Dependencies: FAU_GEN.1 Audit data generation
FIA_UID.1 Timing of identification
FAU_GEN.2.1 For audit events resulting from actions of identified users, the TSF
shall be able to associate each auditable event with the identity
of the user that caused the event.
6.4.2 Cryptographic Support (FCS)
FCS_CKM.1/RSA Cryptographic key generation
Hierarchical to: No other components.
Dependencies: [FCS_CKM.2 Cryptographic key distribution, or
FCS_COP.1 Cryptographic operation]
FCS_CKM.4 Cryptographic key destruction
FCS_CKM.1.1/
RSA
The TSF shall generate RSA cryptographic keys in accordance with
a specified cryptographic key generation algorithm RSA 7 and
specified cryptographic key sizes 2048, 3072, 4096, 8192 bits 8
6 [assignment: Type of action performed (success or failure), identity of the role which performs the
operation]
7 [assignment: cryptographic key generation algorithm]
8 [assignment: cryptographic key sizes]
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that meet the following: TS 119312 [9] PKCS#1 [15] FIPS 186-4
[16]. 9
Application Note 34 (Application Note 32 from [5])
The TOE is expected to use a CM certified in conformance with EN 419 221-5 [7]. See also
OE.CRYPTOMODULE_CERTIFIED for key generation. Although the TSF may not generate
keys itself, these FCS SFRs express the requirement for the TSF to invoke the CM with the
appropriate parameters whenever key generation is required.
Guidance on cryptographic algorithms can be found in ETSI TS 119 312 [9] or SOG-IS [10].
Application Note 35 (Application Note 33 from [5])
Applied.
The ST writer created iterations of this SFR.
FCS_CKM.1/ECDSA Cryptographic key generation
Hierarchical to: No other components.
Dependencies: [FCS_CKM.2 Cryptographic key distribution, or
FCS_COP.1 Cryptographic operation]
FCS_CKM.4 Cryptographic key destruction
FCS_CKM.1.1/
ECDSA
The TSF shall generate ECDSA cryptographic keys in accordance
with a specified cryptographic key generation algorithm ECDSA 10
and specified cryptographic key sizes 192, 224, 256, 384, 521 bits
11 that meet the following: TS 119312 [9] PKCS#1 [15] FIPS 186-4
[16]. 12
FCS_CKM.1/AES Cryptographic key generation
Hierarchical to: No other components.
Dependencies: [FCS_CKM.2 Cryptographic key distribution, or
FCS_COP.1 Cryptographic operation]
FCS_CKM.4 Cryptographic key destruction
FCS_CKM.1.1/
AES
The TSF shall generate AES cryptographic keys in accordance with
a specified cryptographic key generation algorithm AES 13 and
specified cryptographic key sizes 256, 512 bits 14 that meet the
following: SOG-IS [10]. 15
9 [assignment: list of standards]
10 [assignment: cryptographic key generation algorithm]
11 [assignment: cryptographic key sizes]
12 [assignment: list of standards]
13 [assignment: cryptographic key generation algorithm]
14 [assignment: cryptographic key sizes]
15 [assignment: list of standards]
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FCS_CKM.4 Cryptographic key destruction
Hierarchical to: No other components.
Dependencies: [FDP_ITC.1 Import of user data without security attributes, or
FDP_ITC.2 Import of user data with security attributes, or
FCS_CKM.1 Cryptographic key generation]
FCS_CKM.4.1 The TSF shall destroy cryptographic keys in accordance with a
specified cryptographic key destruction method zeroise 16 that
meets the following: FIPS 140-2 [17] 17.
Application Note 36 (Application Note 34 from [5], refined by ST author)
Applied.
The TOE is expected to use a CM certified in conformance with EN 419 221-5 [7] for key
destruction.
Although the TSF may not destruct keys, this SFR expresses the requirement for the TSF to
invoke the CM with the appropriate parameters whenever key destruction is required.
Zeroisation of the keys is the common method of the TOE.
Application Note 37 (Application Note 35 from [5], refined by ST author)
Applied.
Zeroisation of the keys is the common method of the TOE.
FCS_COP.1/DIG_SIG_GEN Cryptographic operation
Hierarchical to: No other components.
Dependencies: [FDP_ITC.1 Import of user data without security attributes, or
FDP_ITC.2 Import of user data with security attributes, or
FCS_CKM.1 Cryptographic key generation]
FCS_CKM.4 Cryptographic key destruction
FCS_COP.1.1/
DIG_SIG_GEN
The TSF shall perform digital signature – generation 18 in
accordance with a specified cryptographic algorithm Table 6-4:
Signature generation algorithm 19 and cryptographic key sizes
Table 6-4: Key sizes 20 that meet the following: Table 6-4:
Applicable standards21.
16 [assignment: cryptographic key destruction method]
17 [assignment: list of standards]
18 [assignment: list of cryptographic operations]
19 [assignment: cryptographic algorithm]
20 [assignment: cryptographic key sizes]
21 [assignment: list of standards]
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Signature generation
algorithm
Key
sizes
Padding / Short
curve name
Hash algorithm Applicable
standards
RSA 2048,
3072,
4096,
8192
bits
RSASSA-PKCS-v1.5
RSASSA-PSS
SHA-224, SHA256,
SHA-384, SHA512
TS 119312 [9]
RSASSA-
PKCS#1v1_5 PKCS#1
[15]
ECDSA 192,
224,
256,
384,
521
bits
NIST P-256, P-384,
P-521
SHA-224, SHA256,
SHA-384, SHA512
FIPS 186-4 [16], ANSI
X9.62 [18]
Table 6-4: Signature generation algorithm
Application Note 38 (Application Note 36 from [5])
The TOE is expected to use a CM certified in conformance with EN 419 221-5 [7] for
cryptographic operations.
Application Note 39 (Application Note 37 from [5])
The relevant authorities and endorsements for completion of the SFRs are determined by
the context of the client applications that use the TOE. For digital signatures within the
European Union, this is as indicated in eIDAS Regulation No 910/2014 [8] and a list of
approved signature and seal formats are given in [13].
Application Note 40 (from ST Author)
Ascertia ADSS Server SAM allows configurations to restrict the use of weaker hash
algorithms. The weaker algorithms are supported just for backward compatibility and
legacy applications.
The Ascertia ADSS Server SAM configuration manual explains how to configure the product
to use the recommended algorithms.
If the TOE uses aforementioned weaker algorithms it is outside of the scope of this ST.
FCS_COP.1/DIG_SIG_VER Cryptographic operation
Hierarchical to: No other components.
Dependencies: [FDP_ITC.1 Import of user data without security attributes, or
FDP_ITC.2 Import of user data with security attributes, or
FCS_CKM.1 Cryptographic key generation]
FCS_CKM.4 Cryptographic key destruction
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FCS_COP.1.1/
DIG_SIG_VER
The TSF shall perform digital signature – verification 22 in
accordance with a specified cryptographic algorithm Table 6-5:
Signature verification algorithm 23 and cryptographic key sizes
Table 6-5: Key sizes 24 that meet the following: Table 6-5:
Applicable standards 25.
Signature verification
algorithm
Key sizes Padding / Short
curve name
Hash
algorithm
Applicable standards
RSA 2048,
3072,
4096, 8192
bits
RSASSA-PKCS-
v1.5
RSASSA-PSS
SHA224,
SHA256,
SHA384,
SHA512
TS 119312 [9] RSASSA-
PKCS#1v1_5 PKCS#1 [15]
ECDSA 192, 224,
256, 384,
521 bits
NIST P-256, P-
384, P-521
SHA224,
SHA256,
SHA384,
SHA512
FIPS 186-4 [16], ANSI X9.62
[18]
Table 6-5: Signature verification algorithm
FCS_COP.1/HASH Cryptographic operation
Hierarchical to: No other components.
Dependencies: [FDP_ITC.1 Import of user data without security attributes, or
FDP_ITC.2 Import of user data with security attributes, or
FCS_CKM.1 Cryptographic key generation]
FCS_CKM.4 Cryptographic key destruction
FCS_COP.1.1/
HASH
The TSF shall perform cryptographic hash function 26 in
accordance with a specified cryptographic algorithm SHA256,
SHA384, SHA512 27 and cryptographic key sizes none 28 that meet
the following: TS 119312 [9], FIPS 186-4 [16] 29.
FCS_COP.1/HMAC Cryptographic operation
Hierarchical to: No other components.
Dependencies: [FDP_ITC.1 Import of user data without security attributes, or
22 [assignment: list of cryptographic operations]
23 [assignment: cryptographic algorithm]
24 [assignment: cryptographic key sizes]
25 [assignment: list of standards]
26 [assignment: list of cryptographic operations]
27 [assignment: cryptographic algorithm]
28 [assignment: cryptographic key sizes]
29 [assignment: list of standards]
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FDP_ITC.2 Import of user data with security attributes, or
FCS_CKM.1 Cryptographic key generation]
FCS_CKM.4 Cryptographic key destruction
FCS_COP.1.1/
HMAC
The TSF shall perform keyed-hash message authentication code
30 in accordance with a specified cryptographic algorithm HMAC-
SHA256 31 and cryptographic key sizes: 256 bit 32 that meet the
following: RFC 2104 [19] 33.
FCS_COP.1/ENC Cryptographic operation
Hierarchical to: No other components.
Dependencies: [FDP_ITC.1 Import of user data without security attributes, or
FDP_ITC.2 Import of user data with security attributes, or
FCS_CKM.1 Cryptographic key generation]
FCS_CKM.4 Cryptographic key destruction
FCS_COP.1.1/
ENC
The TSF shall perform key encryption 34 in accordance with a
specified cryptographic algorithm AES 35 and cryptographic key
sizes 256, 512 bits 36 that meet the following: SOG-IS [10] 37.
The next SFR is relevant when the TOE is deployed in an appliance distinct form the CM.
FCS_RNG.1 Generation of random numbers
Hierarchical to: No other components.
Dependencies: No dependencies.
FCS_RNG.1.1 The TSF shall provide a deterministic 38 random number
generator that implements: securing communication with CM 39.
FCS_RNG.1.2 The TSF shall provide bits 40 that meet BSI AIS 20 v2.0 [20] or NIST
800-90A [21] 41.
Application Note 41 (Application Note 40 from [5])
30 [assignment: list of cryptographic operations]
31 [assignment: cryptographic algorithm]
32 [assignment: cryptographic key sizes]
33 [assignment: list of standards]
34 [assignment: list of cryptographic operations]
35 [assignment: cryptographic algorithm]
36 [assignment: cryptographic key sizes]
37 [assignment: list of standards]
38 [selection: physical, non-physical true, deterministic, hybrid physical, hybrid deterministic
39 [assignment: list of security capabilities]
40 [selection: bits, octets of bits, numbers [assignment: format of the numbers]]
41 [assignment: a defined quality metric]
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For more information on the selections and assignments, see the SFR definition in section
5.
Application Note 42 (Application Note 41 from [5], refined by ST author)
This SFR is not relevant as the TOE is deployed in the same appliance as the CM.Application
Note 43 (from ST Author)
The algorithm to be used can be configured by Ascertia ADSS Server SAM operator. The
Ascertia ADSS Server SAM operator can choose an RNG algorithm from the following
options: -
 HMAC/SHA-256 MAC-based secure random according to NIST SP800-90A; or
 SHA-256 hash-based secure random according to BSI AIS 20 v2.0.
6.4.3 User Data Protection (FDP)
FDP_ACC.1/Privileged User Creation Subset access control
Hierarchical to: No other components.
Dependencies: FDP_ACF.1 Security attribute based access control
FDP_ACC.1.1/
Privileged User
Creation
The TSF shall enforce the Privileged User Creation SFP 42 on: -
Subjects: Privileged User (Operator)
Objects: New security attributes for the Privileged User to be
created.
Operations: Create_New_Privileged_User:
The TOE creates R.Privileged_User and
R.Reference_Privileged_User_Authentication_Data with
information transmitted by Privileged User.43
Application Note 44 (Application Note 42 from [5], refined by ST author)
Applied.
When Ascertia ADSS Server SAM is installed, a default Ascertia ADSS Server SAM Operator
account is automatically created. The default operator logins to the Ascertia ADSS Server
SAM Admin Console and creates Privileged Users (Operators and Business Applications,
see sec. 3.2).
Application Note 45 (from ST Author)
The ST author added refinement (in this and the following SFRs) about which type of
Privileged User (Operator, Business Application) is the relevant.
FDP_ACF.1/Privileged User Creation Security attribute based access control
Hierarchical to: No other components.
42 [assignment: access control SFP]
43 [assignment: list of subjects, objects, and operations among subjects and objects covered by the SFP]
Security Target Ascertia ADSS Server SAM
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Dependencies: FDP_ACC.1 Subset access control
FMT_MSA.3 Static attribute initialisation
FDP_ACF.1.1/
Privileged User
Creation
The TSF shall enforce the Privileged User Creation SFP 44 to
objects based on the following: -
1) whether the subject is a Privileged User (Operator)
authorized to create a new Privileged User. 45
FDP_ACF.1.2/
Privileged User
Creation
The TSF shall enforce the following rules to determine if an
operation among controlled subjects and controlled objects is
allowed: -
1) Only a Privileged User (Operator) who has been
authorised for creation of new users can carry out the
Create_New_Privileged_User operation. 46
FDP_ACF.1.3/
Privileged User
Creation
The TSF shall explicitly authorise access of subjects to objects
based on the following additional rules: None. 47
FDP_ACF.1.4/
Privileged User
Creation
The TSF shall explicitly deny access of subjects to objects based
on the following additional rule: None. 48
FDP_ACC.1/Signer Creation Subset access control
Hierarchical to: No other components.
Dependencies: FDP_ACF.1 Security attribute based access control
FDP_ACC.1.1/
Signer
Creation
The TSF shall enforce the Signer Creation SFP 49 on: -
Subjects: Privileged User (Business Application)
Objects: R.Signer and R.Reference_Signer_Authentication_Data
Operations: Create_New_Signer:
The TOE creates R.Signer and
R.Reference_Signer_Authentication_Data with information
transmitted by Privileged User (Business Application) 50
FDP_ACF.1/Signer Creation Security attribute based access control
Hierarchical to: No other components.
44 [assignment: access control SFP]
45 [assignment: list of subjects and objects controlled under the indicated SFP, and for each, the SFP-
relevant security attributes, or named groups of SFP-relevant security attributes]
46 [assignment: rules governing access among controlled subjects and controlled objects using
controlled operations on controlled objects]
47 [assignment: rules, based on security attributes, that explicitly authorise access of subjects to objects]
48 [assignment: rules, based on security attributes, that explicitly deny access of subjects to objects]
49 [assignment: access control SFP]
50 [assignment: list of subjects, objects, and operations among subjects and objects covered by the SFP]
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Dependencies: FDP_ACC.1 Subset access control
FMT_MSA.3 Static attribute initialisation
FDP_ACF.1.1/
Signer
Creation
The TSF shall enforce the Signer Creation SFP 51 to objects based
on the following: -
1) whether the subject is a Privileged User (Business
Application) authorized to create a new Signer. 52
FDP_ACF.1.2/
Signer
Creation
The TSF shall enforce the following rules to determine if an
operation among controlled subjects and controlled objects is
allowed: -
1) Only a Privileged User (Business Application) who has
been authorised for creation of new users can carry out
the Create_New_Signer operation. 53
FDP_ACF.1.3/
Signer
Creation
The TSF shall explicitly authorise access of subjects to objects
based on the following additional rules: None. 54
FDP_ACF.1.4/
Signer
Creation
The TSF shall explicitly deny access of subjects to objects based
on the following additional rule: None. 55
FDP_ACC.1/Signer Maintenance Subset access control
Hierarchical to: No other components.
Dependencies: FDP_ACF.1 Security attribute based access control
FDP_ACC.1.1/
Signer
Maintenance
The TSF shall enforce the Signer Maintenance SFP 56 on: -
Subjects: Privileged User (Business Application, Operator) and
Signer
Objects: The security attributes
R.Reference_Signer_Authentication_Data of R.Signer
Operations: Signer_Maintenance:
The Privileged User (Business Application, Operator) or Signer
instructs the TOE to update
R.Reference_Signer_Authentication_Data of R.Signer.57
51 [assignment: access control SFP]
52 [assignment: list of subjects and objects controlled under the indicated SFP, and for each, the SFP-
relevant security attributes, or named groups of SFP-relevant security attributes]
53 [assignment: rules governing access among controlled subjects and controlled objects using
controlled operations on controlled objects]
54 [assignment: rules, based on security attributes, that explicitly authorise access of subjects to objects]
55 [assignment: rules, based on security attributes, that explicitly deny access of subjects to objects]
56 [assignment: access control SFP]
57 [assignment: list of subjects, objects, and operations among subjects and objects covered by the SFP]
Security Target Ascertia ADSS Server SAM
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FDP_ACF.1/Signer Maintenance Security attribute based access control
Hierarchical to: No other components.
Dependencies: FDP_ACC.1 Subset access control
FMT_MSA.3 Static attribute initialisation
FDP_ACF.1.1/
Signer
Maintenance
The TSF shall enforce the Signer Maintenance SFP 58 to objects
based on the following:
1) Whether the subject is a Privileged User (Business
Application, Operator) or Signer authorised to maintain
the Signer security attributes. 59
FDP_ACF.1.2/
Signer
Maintenance
The TSF shall enforce the following rules to determine if an
operation among controlled subjects and controlled objects is
allowed:
1) Only a Privileged User (Business Application, Operator) or
Signer who has been authorised to maintain a Signer can
carry out the Signer_Maintenance operation. 60
FDP_ACF.1.3/
Signer
Maintenance
The TSF shall explicitly authorise access of subjects to objects
based on the following additional rules:
1) The Signer must be the owner of the R.Signer object to be
maintained.61
FDP_ACF.1.4/
Signer
Maintenance
The TSF shall explicitly deny access of subjects to objects based
on the following additional rules:
1) If the Signer does not own the R.Signer object, it can’t be
maintained.62
Application Note 46 (Application Note 43 from [5], refined by ST author)
R.Reference_Signer_Authentication Data can be maintained by only the Privileged User
(Business Application and Operator).
FDP_ACC.1/Signer Key Pair Generation Subset access control
Hierarchical to: No other components.
Dependencies: FDP_ACF.1 Security attribute based access control
58 [assignment: access control SFP]
59 [assignment: list of subjects and objects controlled under the indicated SFP, and for each, the SFP-
relevant security attributes, or named groups of SFP-relevant security attributes]
60 [assignment: rules governing access among controlled subjects and controlled objects using
controlled operations on controlled objects]
61 [assignment: rules, based on security attributes, that explicitly authorise access of subjects to objects]
62 [assignment: rules, based on security attributes, that explicitly deny access of subjects to objects]
Security Target Ascertia ADSS Server SAM
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FDP_ACC.1.1/
Signer Key Pair
Generation
The TSF shall enforce the Signer Key Pair Generation SFP 63 on: -
Subjects: Privileged User (Business Application) and Signer.
Objects: The security attributes R.SVD and R.Signing_Key_Id as
part of R.Signer.
Operations: Generate_Signer_Key_Pair:
The Privileged User (Business Application) or Signer instruct the
TOE to request the Cryptographic Module to generate a signing
key pair R.Signing_Key_Id and R.SVD and assign them to the
R.Signer. 64
Application Note 47 (Application Note 44 from [5], refined by ST author)
Applied.
See Application Note 2 in sec. 3.1 Assets.
Application Note 48 (Application Note 45 from [5], refined by ST author)
Applied.
See R.Authorisation_Data. The user’s signing keys can be backed-up from one CM and
imported to another CM.
Application Note 49 (Application Note 46 from [5], refined by ST author)
Applied.
The TOE does not use pre-generated keys.
Application Note 50 (Application Note 47 from [5], refined by ST author)
Applied.
The R.SVD is added to the CSR to get the signing certificate from an issuing CA.
Application Note 51 (from ST Author)
The key pair generation request can be immediately sent after the user details are
registered or it can be initiated later depending on business application implementation.
Therefore, the Signer creation process is two-step process in the TOE and these are
covered by FDP_ACC.1/Signer_Creation and FDP_ACC.1/Signer Key Pair Generation.
FDP_ACF.1/Signer Key Pair Generation Security attribute based access control
Hierarchical to: No other components.
Dependencies: FDP_ACC.1 Subset access control
FMT_MSA.3 Static attribute initialisation
63 [assignment: access control SFP]
64 [assignment: list of subjects, objects, and operations among subjects and objects covered by the SFP]
Security Target Ascertia ADSS Server SAM
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FDP_ACF.1.1/
Signer Key Pair
Generation
The TSF shall enforce the Signer Key Pair Generation SFP 65 to
objects based on the following: -
1) whether the subject is a Privileged User (Business
Application) or Signer authorised to generate a key pair.
66
FDP_ACF.1.2/
Signer Key Pair
Generation
The TSF shall enforce the following rules to determine if an
operation among controlled subjects and controlled objects is
allowed: -
1) Only a Privileged User (Business Application) or Signer
who has been authorised to generate the key pair can
carry out the Generate_Signer_Key_Pair operation. 67
FDP_ACF.1.3/
Signer Key Pair
Generation
The TSF shall explicitly authorise access of subjects to objects
based on the following additional rules: -
1) The Signer must be the owner of the R.Signer object where
the key pair is to be generated. 68
FDP_ACF.1.4/
Signer Key Pair
Generation
The TSF shall explicitly deny access of subjects to objects based
on the following additional rules: -
1) If the Signer does not own the R.Signer object, key pair
shall not be generated. 69
Application Note 52 (Application Note 48 from [5], refined by ST author)
Applied.
The TOE does not use pre-generated keys.
Application Note 53 (Application Note 49 from [5])
Owning an R.Signer object is described in FIA_UAU.5/Signer.
FDP_ACC.1/Signer Key Pair Deletion Subset access control
Hierarchical to: No other components.
Dependencies: FDP_ACF.1 Security attribute based access control
FDP_ACC.1.1/
Signer Key Pair
Deletion
The TSF shall enforce the Signer Key Pair Deletion SFP 70 on: -
Subjects: Privileged User (Business Application, Operator) and
Signer
65 [assignment: access control SFP]
66 [assignment: list of subjects and objects controlled under the indicated SFP, and for each, the SFP-
relevant security attributes, or named groups of SFP-relevant security attributes]
67 [assignment: rules governing access among controlled subjects and controlled objects using
controlled operations on controlled objects]
68 [assignment: rules, based on security attributes, that explicitly authorise access of subjects to objects]
69 [assignment: rules, based on security attributes, that explicitly deny access of subjects to objects]
70 [assignment: access control SFP]
Security Target Ascertia ADSS Server SAM
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Objects: The security attributes R.Signing_Key_Id and R.SVD of
R.Signer
Operations: Signer_Key_Pair_Deletion:
The Privileged User (Business Application, Operator) or Signer
instructs the TOE to delete the R.Signing_Key_Id and R.SVD of
R.Signer.71
Application Note 54 (Application Note 50 from [5], refined by ST author)
Applied. Not required.
This SFR is limited to covering deletion of the R.Signing_Key_Id and R.SVD of R.Signer
performed using one of the interfaces provided by the TOE and where authorisation to
perform operations is managed by TOE.
FDP_ACF.1/Signer Key Pair Deletion Security attribute based access control
Hierarchical to: No other components.
Dependencies: FDP_ACC.1 Subset access control
FMT_MSA.3 Static attribute initialisation
FDP_ACF.1.1/
Signer Key Pair
Deletion
The TSF shall enforce the Signer Key Pair Deletion SFP 72 to objects
based on the following: -
1) Whether the subject is a Privileged User (Business
Application, Operator) or Signer authorised to delete the
Signer security attributes. 73
FDP_ACF.1.2/
Signer Key Pair
Deletion
The TSF shall enforce the following rules to determine if an
operation among controlled subjects and controlled objects is
allowed: -
1) Only a Privileged User (Business Application, Operator) or
Signer who has been authorised to delete a key pair can
carry out the Signer_Key_Pair_Deletion operation. 74
FDP_ACF.1.3/
Signer Key Pair
Deletion
The TSF shall explicitly authorise access of subjects to objects
based on the following additional rules: -
1) The Signer must be the owner of the R.Signer object
containing the key pair to be deleted. 75
71 [assignment: list of subjects, objects, and operations among subjects and objects covered by the SFP]
72 [assignment: access control SFP]
73 [assignment: list of subjects and objects controlled under the indicated SFP, and for each, the SFP-
relevant security attributes, or named groups of SFP-relevant security attributes]
74 [assignment: rules governing access among controlled subjects and controlled objects using
controlled operations on controlled objects]
75 [assignment: rules, based on security attributes, that explicitly authorise access of subjects to objects]
Security Target Ascertia ADSS Server SAM
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FDP_ACF.1.4/
Signer Key Pair
Deletion
The TSF shall explicitly deny access of subjects to objects based
on the following additional rules: -
1) If the Signer does not own the R.Signer object, the key pair
can’t be deleted. 76
The DTBS/R can be supplied to the TOE either by the Signer as part of the SAP, which is
covered by the FDP_ACC.1/Signing or by a Privileged User prior the signature operation.
The following SFR handles the case where the Privileged User supplies the DTBS/R.
FDP_ACC.1/Supply DTBS/R Subset access control
Hierarchical to: No other components.
Dependencies: FDP_ACF.1 Security attribute based access control
FDP_ACC.1.1/
Supply DTBS/R
The TSF shall enforce the Supply DTBS/R SFP 77 on: -
Subjects: Privileged User (Business Application)
Objects: The security attributes R.DTBS/R of R.Signer.
Operations: Supply_DTBS/R:
The Privileged User (Business Application) instructs the TOE to
link the supplied DTBS/R(s) to the next signature operation for
R.Signer.78
Application Note 55 (Application Note 51 from [5], refined by ST author)
Applied. The TOE provides facilities to supply the DTBS/R.
FDP_ACF.1/Supply DTBS/R Security attribute based access control
Hierarchical to: No other components.
Dependencies: FDP_ACC.1 Subset access control
FMT_MSA.3 Static attribute initialisation
FDP_ACF.1.1/
Supply DTBS/R
The TSF shall enforce the Supply DTBS/R SFP 79 to objects based
on the following: -
1) Whether the subject is a Privileged User (Business
Application) authorised to supply a DTBS/R(s). 80
76 [assignment: rules, based on security attributes, that explicitly deny access of subjects to objects]
77 [assignment: access control SFP]
78 [assignment: list of subjects, objects, and operations among subjects and objects covered by the SFP]
79 [assignment: access control SFP]
80 [assignment: list of subjects and objects controlled under the indicated SFP, and for each, the SFP-
relevant security attributes, or named groups of SFP-relevant security attributes]
Security Target Ascertia ADSS Server SAM
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FDP_ACF.1.2/
Supply DTBS/R
The TSF shall enforce the following rules to determine if an
operation among controlled subjects and controlled objects is
allowed: -
1) Only a Privileged User (Business Application) who has
been authorised to supply a DTBS/R(s) can carry out the
Supply_DTBS/R operation. 81
FDP_ACF.1.3/
Supply DTBS/R
The TSF shall explicitly authorise access of subjects to objects
based on the following additional rules: None. 82
FDP_ACF.1.4/
Supply DTBS/R
The TSF shall explicitly deny access of subjects to objects based
on the following additional rules: None. 83
Application Note 56 (Application Note 52 from [5], refined by ST author)
Applied. The TOE provides facilities to supply the DTBS/R.
FDP_ACC.1/Signing Subset access control
Hierarchical to: No other components.
Dependencies: FDP_ACF.1 Security attribute based access control
FDP_ACC.1.1/
Signing
The TSF shall enforce the Signing SFP 84 on: -
Subjects: Signer
Objects: R.Authorisation Data security attributes,
R.Signing_Key_Id and R.DTBS/R of R.Signer and R.Signature.
Operations: Signing:
The Signer instructs the TOE to perform a signature operation
containing the following steps:
 The TOE establishes R.Authorisation_Data for the
R.Signing_Key_Id.
 The TOE uses the R.Authorisation_Data and
R.Signing_Key_Id to activate a signing key in the
Cryptographic Module and signs the R.DTBS/R resulting in
R.Signature.
 The TOE deactivates the signing key when the signature
operation is completed. 85
Application Note 57 (Application Note 53 from [5], refined by ST author)
Applied. See Application Note 2 in sec. 3.1 Assets.
81 [assignment: rules governing access among controlled subjects and controlled objects using
controlled operations on controlled objects]
82 [assignment: rules, based on security attributes, that explicitly authorise access of subjects to objects]
83 [assignment: rules, based on security attributes, that explicitly deny access of subjects to objects]
84 [assignment: access control SFP]
85 [assignment: list of subjects, objects, and operations among subjects and objects covered by the SFP]
Security Target Ascertia ADSS Server SAM
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Application Note 58 (Application Note 54 from [5], refined by ST author)
Applied.
The Business Application (SCA) provides the document hash, i.e. DTBS/R, to RAS Service
(SSA) which passes it to the TOE for signature computation.
Application Note 59 (Application Note 55 from [5])
Signing key deactivation means that the Signer shall authorise any subsequent use of it.
FDP_ACF.1/Signing Security attribute based access control
Hierarchical to: No other components.
Dependencies: FDP_ACC.1 Subset access control
FMT_MSA.3 Static attribute initialisation
FDP_ACF.1.1/
Signing
The TSF shall enforce the Signing SFP 86 to objects based on the
following: -
1) Whether the subject is a Signer authorised to create a
signature. 87
FDP_ACF.1.2/
Signing
The TSF shall enforce the following rules to determine if an
operation among controlled subjects and controlled objects is
allowed: -
1) The R.SAD is verified in integrity.
2) The R.SAD is verified that it binds together the Signer
authentication, a set of R.DTBS/R and R.Signing_Key_Id.
3) The R.DTBS/R used for signature operations is bound to
the R.SAD.
4) The Signer identified in the SAD is authenticated according
to the rules specified in FIA_UAU.5/Signer.
5) Only an R.Signing_Key_Id as bound in the SAD, and which
is part of the R.Signer security attributes, can be used to
create a signature. 88
FDP_ACF.1.3/
Signing
The TSF shall explicitly authorise access of subjects to objects
based on the following additional rules: -
86 [assignment: access control SFP]
87 [assignment: list of subjects and objects controlled under the indicated SFP, and for each, the SFP-
relevant security attributes, or named groups of SFP-relevant security attributes]
88 [assignment: rules governing access among controlled subjects and controlled objects using
controlled operations on controlled objects]
Security Target Ascertia ADSS Server SAM
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1) The Signer must be the owner of the R.Signer object used
to generate the signature. 89
FDP_ACF.1.4/
Signing
The TSF shall explicitly deny access of subjects to objects based
on the following additional rules: -
1) If the Signer does not own the R.Signer object, it can’t be
used to create a signature. 90
Application Note 60 (Application Note 56 from [5], refined by ST author)
Applied. The R.Signing_Key_Id implied.
FDP_ACC.1/TOE Maintenance Subset access control
Hierarchical to: No other components.
Dependencies: FDP_ACF.1 Security attribute based access control
FDP_ACC.1.1/
Maintenance
The TSF shall enforce the TOE Maintenance SFP 91 on:
Subjects: Privileged User (Operator)
Objects: R.TSF_DATA.
Operations: TOE_Maintenance:
The Privileged User (Operator) transmits information to the TOE
to manage R.TSF_DATA.92
FDP_ACF.1/TOE Maintenance Security attribute based access control
Hierarchical to: No other components.
Dependencies: FDP_ACC.1 Subset access control
FMT_MSA.3 Static attribute initialisation
FDP_ACF.1.1/
TOE
Maintenance
The TSF shall enforce the TOE Maintenance SFP 93 to objects
based on the following:
1) Whether the subject is a Privileged User (Operator)
authorised to maintain the TOE configuration data. 94
FDP_ACF.1.2/
TOE
Maintenance
The TSF shall enforce the following rules to determine if an
operation among controlled subjects and controlled objects is
allowed: -
89 [assignment: rules, based on security attributes, that explicitly authorise access of subjects to objects]
90 [assignment: rules, based on security attributes, that explicitly deny access of subjects to objects]
91 [assignment: access control SFP]
92 [assignment: list of subjects, objects, and operations among subjects and objects covered by the SFP]
93 [assignment: access control SFP]
94 [assignment: list of subjects and objects controlled under the indicated SFP, and for each, the SFP-
relevant security attributes, or named groups of SFP-relevant security attributes]
Security Target Ascertia ADSS Server SAM
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1) Only a Privileged User (Operator) who has been
authorised to maintain the TOE can carry out the
TOE_Maintenance operation. 95
FDP_ACF.1.3/
TOE
Maintenance
The TSF shall explicitly authorise access of subjects to objects
based on the following additional rules: None. 96
FDP_ACF.1.4/
TOE
Maintenance
The TSF shall explicitly deny access of subjects to objects based
on the following additional rules: None. 97
The TOE can store data in an external repository to meet requirements on, e.g. capacity
and redundancy.
FDP_ETC.2/Signer Export of user data with security attributes
Hierarchical to: No other components.
Dependencies: [FDP_ACC.1 Subset access control, or
FDP_IFC.1 Subset information flow control]
FDP_ETC.2.1/
Signer
The TSF shall enforce the Signer Creation SFP, Signer Key Pair
Generation SFP, Signer Key Pair Deletion SFP, Signer
Maintenance SFP, Supply DTBS/R SFP and Signing SFP 98
when exporting user data, controlled under the SFP(s),
outside of the TSF.
FDP_ETC.2.2/
Signer
The TSF shall export the user data with the user data's
associated security attributes.
FDP_ETC.2.3/
Signer
The TSF shall ensure that the security attributes, when
exported outside the TSF, are unambiguously associated
with the exported user data.
FDP_ETC.2.4/
Signer
The TSF shall enforce the following rules when user data is
exported from the TSF: None. 99
Application Note 61 (Application note 57 from [5], refined by ST author)
The TOE does not export user data then this SFR is trivially satisfied.
FDP_IFC.1/Signer Subset information flow control
95 [assignment: rules governing access among controlled subjects and controlled objects using
controlled operations on controlled objects]
96 [assignment: rules, based on security attributes, that explicitly authorise access of subjects to objects]
97 [assignment: rules, based on security attributes, that explicitly deny access of subjects to objects]
98 [assignment: access control SFP(s) and/or information flow control SFP(s)]
99 [assignment: additional exportation control rules]
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Hierarchical to: No other components.
Dependencies: FDP_IFF.1 Simple security attributes
FDP_IFC.1.1/
Signer
The TSF shall enforce the Signer Flow SFP 100 on Privileged User
(Business Application and Operator) and Signer accessing Signer
security attributes for all operations. 101
FDP_IFF.1/Signer Simple security attributes
Hierarchical to: No other components.
Dependencies: FDP_IFC.1 Subset information flow control, or
FMT_MSA.3 Static attribute initialisation
FDP_IFF.1.1/
Signer
The TSF shall enforce the Signer Flow SFP 102 based on the
following types of subject and information security attributes: -
Privileged User (Business Application and Operator) and Signer
accessing the Signer security attributes. 103
FDP_IFF.1.2/
Signer
The TSF shall permit an information flow between a controlled
subject and controlled information via a controlled operation if
the following rules hold:
The TOE shall be initialized with FDP_ACC.1/TOE Maintenance.
To allow a Signer to sign, the Signer shall be created in the TOE by
FDP_ACC.1/Signer Creation followed by FDP_ACC.1/Signer key
Pair Generation.
After Signer is created the following operations can be done:
FDP_ACC.1/Signer Key Pair Generation, FDP_ACC.1/Signer Key
Pair Deletion, FDP_ACC.1/Supply DTBS/R, FDP_ACC.1/Signer
Maintenance and FDP_ACC.1/Signing. 104
FDP_IFF.1.3/
Signer
The TSF shall enforce the: None. 105
FDP_IFF.1.4/
Signer
The TSF shall explicitly authorise an information flow based on
the following rules: None. 106
100 [assignment: information flow control SFP]
101 [assignment: list of subjects, information, and operations that cause controlled information to flow to
and from controlled subjects covered by the SFP]
102 [assignment: information flow control SFP]
103 [assignment: list of subjects and information controlled under the indicated SFP, and for each, the
security attributes]
104 [assignment: for each operation, the security attribute-based relationship that must hold between
subject and information security attributes]
105 [assignment: additional information flow control SFP rules]
106 [assignment: rules, based on security attributes, that explicitly authorise information flows]
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FDP_IFF.1.5/
Signer
The TSF shall explicitly deny an information flow based on the
following rules: None. 107
FDP_ETC.2/Privileged User Export of user data with security attributes
Hierarchical to: No other components.
Dependencies: [FDP_ACC.1 Subset access control, or
FDP_IFC.1 Subset information flow control]
FDP_ETC.2.1/
Privileged User
The TSF shall enforce the Privileged User Creation SFP 108 when
exporting user data, controlled under the SFP(s), outside of the
TSF.
FDP_ETC.2.2/
Privileged User
The TSF shall export the user data with the user data's associated
security attributes.
FDP_ETC.2.3/
Privileged User
The TSF shall ensure that the security attributes, when exported
outside the TSF, are unambiguously associated with the exported
user data.
FDP_ETC.2.4/
Privileged User
The TSF shall enforce the following rules when user data is
exported from the TSF: None. 109
Application Note 62 (Application Note 58 from [5], refined by ST author)
The ST writer shall describe which user data that can be exported from the TOE. The
following Privileged User data can be exported from the TOE:
 Data of Operator: Id, FirstName, LastName, RoleName, EmailAddress, MobileNo,
CertificateRequest, Certificate, CertificateChain, SubjectName, Status, CreatedAt,
CreatedBy, LastUpdatedAt, LastUpdatedBy.
 Data of Business Application: Id, FriendlyName, Address, PhoneNo, EmailAddress,
Status, AssignedSamProfiles, Certificate, ValidFrom, ValidTo
The Privileged User data can be exported in an XML format just like TOE configuration
data. This XML later can be imported to another instance of the TOE.
FDP_IFC.1/Privileged user Subset information flow control
Hierarchical to: No other components.
Dependencies: FDP_IFF.1 Simple security attributes
107 [assignment: rules, based on security attributes, that explicitly deny information flows]
108 [assignment: access control SFP(s) and/or information flow control SFP(s)]
109 [assignment: additional exportation control rules]
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FDP_IFC.1.1/
Privileged User
The TSF shall enforce the Privileged User Flow SFP 110 on
Privileged User (Operator) accessing Privileged User security
attributes for all operations. 111
FDP_IFF.1/Privileged User Simple security attributes
Hierarchical to: No other components.
Dependencies: FDP_IFC.1 Subset information flow control, or
FMT_MSA.3 Static attribute initialisation
FDP_IFF.1.1/
Privileged User
The TSF shall enforce the Privileged User Flow SFP 112 based on
the following types of subject and information security
attributes: -
Privileged User (Operator) accessing the Privileged User security
attributes. 113
FDP_IFF.1.2/
Privileged User
The TSF shall permit an information flow between a controlled
subject and controlled information via a controlled operation if
the following rules hold: -
The TOE shall be initialized with FDP_ACC.1/TOE Maintenance. 114
FDP_IFF.1.3/
Privileged User
The TSF shall enforce the: None. 115
FDP_IFF.1.4/
Privileged User
The TSF shall explicitly authorise an information flow based on
the following rules: None. 116
FDP_IFF.1.5/
Privileged User
The TSF shall explicitly deny an information flow based on the
following rules: None. 117
FDP_ITC.2/Signer Import of user data with security attributes
Hierarchical to: No other components.
Dependencies: [FDP_ACC.1 Subset access control, or
FDP_IFC.1 Subset information flow control]
110 [assignment: information flow control SFP]
111 [assignment: list of subjects, information, and operations that cause controlled information to flow to
and from controlled subjects covered by the SFP]
112 [assignment: information flow control SFP]
113 [assignment: list of subjects and information controlled under the indicated SFP, and for each, the
security attributes]
114 [assignment: for each operation, the security attribute-based relationship that must hold between
subject and information security attributes]
115 [assignment: additional information flow control SFP rules]
116 [assignment: rules, based on security attributes, that explicitly authorise information flows]
117 [assignment: rules, based on security attributes, that explicitly deny information flows]
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[FTP_ITC.1 Inter-TSF Trusted channel, or
FTP_TRP.1 Trusted path]
FPT_TDC.1 Inter-TSF basic TSF data consistency
FDP_ITC.2.1/
Signer
The TSF shall enforce the Signer Creation SFP, Signer Key Pair
Generation SFP, Signer Key Pair Deletion, Signer Maintenance
SFP, Supply DTBS/R SFP and Signing SFP 118 when importing user
data, controlled under the SFP, from outside of the TOE.
FDP_ITC.2.2/
Signer
The TSF shall use the security attributes associated with the
imported user data.
FDP_ITC.2.3/
Signer
The TSF shall ensure that the protocol used provides for the
unambiguous association between the security attributes and
the user data received.
FDP_ITC.2.4/
Signer
The TSF shall ensure that interpretation of the security attributes
of the imported user data is as intended by the source of the user
data.
FDP_ITC.2.5/
Signer
The TSF shall enforce the following rules when importing user
data controlled under the SFP from outside the TOE: None. 119
Application Note 63 (Application Note 59 from [5], refined by ST author)
The TOE does not import user data then this SFR is trivially satisfied.
FDP_ITC.2/Privileged User Import of user data with security attributes
Hierarchical to: No other components.
Dependencies: [FDP_ACC.1 Subset access control, or
FDP_IFC.1 Subset information flow control]
[FTP_ITC.1 Inter-TSF Trusted channel, or
FTP_TRP.1 Trusted path]
FPT_TDC.1 Inter-TSF basic TSF data consistency
FDP_ITC.2.1/
Privileged User
The TSF shall enforce the Privileged User Creation SFP 120 when
importing user data, controlled under the SFP, from outside of
the TOE.
FDP_ITC.2.2/
Privileged User
The TSF shall use the security attributes associated with the
imported user data.
118 [assignment: access control SFP(s) and/or information flow control SFP(s)]
119 [assignment: additional importation control rules]
120 [assignment: access control SFP(s) and/or information flow control SFP(s)]
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FDP_ITC.2.3/
Privileged User
The TSF shall ensure that the protocol used provides for the
unambiguous association between the security attributes and
the user data received.
FDP_ITC.2.4/
Privileged User
The TSF shall ensure that interpretation of the security attributes
of the imported user data is as intended by the source of the user
data.
FDP_ITC.2.5/
Privileged User
The TSF shall enforce the following rules when importing user
data controlled under the SFP from outside the TOE: None. 121
Application Note 64 (Application Note 60 from [5], refined by ST author)
The ST writer shall describe which user data that can be imported to the TOE. The following
Privileged User data can be imported to the TOE:
 Data of Operator: Id, FirstName, LastName, RoleName, EmailAddress, MobileNo,
CertificateRequest, Certificate, CertificateChain, SubjectName, Status, CreatedAt,
CreatedBy, LastUpdatedAt, LastUpdatedBy.
 Data of Business Application: Data of Business Application: Id, FriendlyName,
Address, PhoneNo, EmailAddress, Status, AssignedSamProfiles, Certificate,
ValidFrom, ValidTo
FDP_UCT.1 Basic data exchange confidentiality
Hierarchical to: No other components.
Dependencies: [FTP_ITC.1 Inter-TSF Trusted channel, or
FTP_TRP.1 Trusted path]
[FDP_ACC.1 Subset access control, or
FDP_IFC.1 Subset information flow control]
FDP_UCT.1.1 The TSF shall enforce the Signer Flow SFP and Privileged User
Flow SFP 122 to transmit and receive 123 user data in a manner
protected from unauthorised disclosure.
FDP_UIT.1 Data exchange integrity
Hierarchical to: No other components.
Dependencies: [FDP_ACC.1 Subset access control, or
FDP_IFC.1 Subset information flow control]
121 [assignment: additional importation control rules]
122 [assignment: access control SFP(s) and/or information flow control SFP(s)]
123 [selection: transmit, receive]
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[FTP_ITC.1 Inter-TSF Trusted channel, or
FTP_TRP.1 Trusted path]
FDP_UIT.1.1 The TSF shall enforce the Signer Flow SFP and Privileged User
Flow SFP 124 to be able to transmit and receive 125 user data in a
manner protected from modification and insertion 126 errors for
R.Signer and R.Privileged User and for R.SAD also from
modification and replay errors.
FDP_UIT.1.2 The TSF shall be able to determine on receipt of user data,
whether modification, deletion and insertion 127 for R.Signer and
R.Privileged_User and for R.SAD for modification and replay has
occurred.
Application Note 65 (Application Note 61 from [5])
Insertion of objects would mean that authorised creation of Signer and Privileged User
could be possible.
6.4.4 Identification & Authentication (FIA)
FIA_AFL.1/BA Authentication failure handling
Hierarchical to: No other components.
Dependencies: FIA_UAU.1 Timing of authentication
FIA_AFL.1.1 /
BA
The TSF shall detect when the fails to authentication to the
Ascertia ADSS Server SAM 128 unsuccessful authentication
attempts occur related to Privileged User (Business Application)
and Signer authentication. 129
FIA_AFL.1.2 /
BA
When the defined number of unsuccessful authentication
attempts has been met 130, the TSF shall suspend the Privileged
User (Business Application) with marks it inactive and when it is
a Signer suspend the usage of R.Signing_Key_Id 131
Application Note 66 (Application Note 62 from [5], refined by ST author)
Applied. The ST writer extended and iterated the FIA_AFL.1 to introduce the operations.
Application Note 67 (Application Note 63 from [5], refined by ST author)
Applied. The TOE uses direct authentication.
124 [assignment: access control SFP(s) and/or information flow control SFP(s)]
125 [selection: transmit, receive]
126 [selection: modification, deletion, insertion, replay]
127 [selection: modification, deletion, insertion, replay]
128 [selection: [assignment: positive integer number], a TOE Maintenance configurable positive within
[assignment: range of acceptable values]]
129 [assignment: list of authentication events]
130 [selection: met, surpassed]
131 [assignment: list of actions]
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Application Note 68 (from ST Author)
For operator authentication the TSF relies on the underlying smartcard/token holding the
operator’s TLS client authentication key/certificate how many unsuccessful login attempt
does it allow to an operator before card/token is locked. This limit may vary from device
to device. The Operator cannot be identified in case of wrong certificate and it’s not
possible to count the number of tries. That is why FIA_AFL.1 is not iterated to Operator.
Application Note 69 (from ST Author)
Refined the original description from the [5] to specify the detection of the failing of the
Privileged User (Business Application) authentication.
Application Note 70 (from ST Author)
The Privileged User (Operator) can activate the Privileged User (Business Application)
when it is inactive.
FIA_AFL.1/Signer Authentication failure handling
Hierarchical to: No other components.
Dependencies: FIA_UAU.1 Timing of authentication
FIA_AFL.1.1 /
Signer
The TSF shall detect when a TOE Maintenance configurable
positive integer defined in the Global Settings of ADSS Server
SAM (R.TSF_DATA) 132 unsuccessful authentication attempts
occur related to Privileged User and Signer authentication. 133
FIA_AFL.1.2 /
Signer
When the defined number of unsuccessful authentication
attempts has been met 134, the TSF shall block the Signer for an
amount of period defined in the Global Settings of ADSS Server
SAM (R.TSF_DATA) suspend the Privileged User and when it is a
Signer suspend the usage of R.Signing_Key_Id. 135
Application Note 71 (from ST Author)
Refined the original description from the [5] to specify the detection of the failing of the
Signer authentication.
FIA_ATD.1 User attribute definition
Hierarchical to: No other components.
Dependencies: No dependencies.
132 [selection: [assignment: positive integer number], a TOE Maintenance configurable positive within
[assignment: range of acceptable values]]
133 [assignment: list of authentication events]
134 [selection: met, surpassed]
135 [assignment: list of actions]
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FIA_ATD.1.1 The TSF shall maintain the following list of security attributes
belonging to individual users: the security attribute as defined in
FIA_USB.1. 136
FIA_UAU.1 Timing of authentication
Hierarchical to: No other components.
Dependencies: FIA_UID.1 Timing of identification
FIA_UAU.1.1 The TSF shall allow
1) Establishing a trusted path between: -
a. remote Signer and the TOE by means of TSF
required by FTP_TRP.1/SIC.
b. Privileged User (Operator and Business
application) and the TOE by means of TSF required
by FTP_TRP.1/SSA.
2) Identification of the user by means of TSF required by
FIA_UID.2 137
on behalf of the user to be performed before the user is
authenticated.
FIA_UAU.1.2 The TSF shall require each user to be successfully authenticated
before allowing any other TSF-mediated actions on behalf of that
user.
FIA_UAU.5/Signer Multiple authentication mechanisms
Hierarchical to: No other components.
Dependencies: No dependencies.
FIA_UAU.5.1/
Signer
The TSF shall provide two OTPs (one sent on Signer’s mobile
number and other on Signer’s email) with mobile device
authentication using biometric fingerprint/faceID or device PIN
authentication when a new mobile device is used 138 to support
Signer authentication.
FIA_UAU.5.2/
Signer
The TSF shall authenticate any Signer's claimed identity
according to the following: -
 the Signer provides fingerprint (inherence authentication
factor); and
136 [assignment: list of security attributes]
137 [assignment: list of TSF mediated actions]
138 [selection: [assignment: list of direct authentication mechanisms conformant to EN 419 241-1 [6]
SRA_SAP.1.1, [assignment: list of delegated authentication mechanisms conformant to EN 419 241-1
[6] SRA_SAP.1.1]]
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 the Signer provides OTPs (possession-based
authentication factor) when a new mobile device is used.
139
Application Note 72 (Application Note 64 from [5], refined by ST author)
Applied. This SFR only applies to Signer authentication for signing (FDP_ACC.1/Signing).
The TOE does not use delegated authentication.
Successful authentication gives Signer access to the relevant R.Signer object as the owner.
The above mentioned authentication mechanisms are used to register a device. After the
registration process has successfully finished the Signer will authenticate himself accessing
the mobiles secure element and signing SAD with his authorisation key.
FIA_UAU.5/Privileged User Multiple authentication mechanisms
Hierarchical to: No other components.
Dependencies: No dependencies.
FIA_UAU.5.1/
Privileged User
The TSF shall provide: -
1) The authentication is done using TLS client certificate
2) The certificate is read from a card which is PIN protected
to support Privileged User (Operator) authentication;
1) The authentication is done using TLS client certificate 140
to support Privileged User (Business Application) authentication.
FIA_UAU.5.2/
Privileged User
The TSF shall authenticate any Privileged User's claimed identity
according to the following: Privileged User uses its TLS
authentication certificate. 141
Application Note 73 (from ST Author)
The ST author refined this SFR to separate the two types of Privileged Users.
FIA_UID.2 User identification before any action
Hierarchical to: FIA_UID.1 Timing of identification.
Dependencies: No dependencies.
FIA_UID.2.1 The TSF shall require each user to be successfully identified
before allowing any other TSF-mediated actions on behalf of that
user.
139 [selection: [assignment:the rules describing how delegated authentication is verified by the TSF],
[assignment: the rules describing how direct authentication mechanisms provide authentication]]
140 [assignment: list of authentication mechanisms]
141 [assignment: rules describing how the multiple authentication mechanisms provide authentication]
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FIA_USB.1 User-subject binding
Hierarchical to: No other components.
Dependencies: FIA_ATD.1 User attribute definition.
FIA_USB.1.1 The TSF shall associate the following user security attributes with
subjects acting on the behalf of that user:
1) R.Reference_Signer_Authentication_Data;
2) R.Signing_Key_Id;
3) R.SVD;
4) R.Signer; and
5) R. Authorisation_Data 142
to Signer: -
1) R.Reference_Priviliged_User_Authentication_Data; and
2) R.Privileged_User 143
to Privileged User. 144
FIA_USB.1.2 The TSF shall enforce the following rules on the initial association
of user security attributes with subjects acting on the behalf of
users: -
1) Whether the subject is a Privileged User (Business
Application) authorized to create a new Signer.
2) Whether the subject is a Privileged User (Operator)
authorized to create a new Privileged User (Business
Application or Operator).
3) None 145 146
FIA_USB.1.3 The TSF shall enforce the following rules governing changes to
the user security attributes associated with subjects acting on the
behalf of users: -
1) Whether the subject is a Privileged User (Business
Application, Operator) authorized to modify an R.Signer
object.
2) Whether the subject is a Signer authorized to modify his
own R.Signer object.
142 [assignment: list of user security attributes]
143 [assignment: list of user security attributes]
144 [assignment: list of user security attributes]
145 [assignment: rules for the initial association of attributes]
146 [assignment: rules for the initial association of attributes]
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3) None 147 148
Application Note 74 (Application Note 65 from [5])
In FIA_USB.1.2 several attributes including R.Signing_Key_ID, R.SVD and R.DTBS/R may
initially be empty.
Application Note 75 (Application Note 66 from [5], refined by ST author)
Applied. Detailed information about R.Authorisation_Data in Application Note 2 in sec.
3.1.
Application Note 76 (Application Note 67 from [5], refined by ST author)
Applied. The Business Application (SCA) provides the document hash (DTBS/R) to RAS
Service (SSA) which passes it to the TOE for signature computation.
6.4.5 Security Management (FMT)
FMT_MSA.1/Signer Management of security attributes
Hierarchical to: No other components.
Dependencies: [FDP_ACC.1 Subset access control, or
FDP_IFC.1 Subset information flow control]
FMT_SMR.1 Security roles
FMT_SMF.1 Specification of Management Functions
FMT_MSA.1.1/
Signer
The TSF shall enforce the: -
1) Signer Creation SFP 149 to restrict the ability to create 150
the security attributes listed in FIA_USB.1 for Signer 151 to
authorised Privileged User (Business Application) 152.
2) Generate Signer Key Pair SFP 153 to restrict the ability to
generate 154 the security attributes R.SVD and
R.Signing_Key_Id as part of R.Signer 155 to authorised
Privileged User (Business Application) and Signer 156.
147 [assignment: rules for the changing of attributes]
148 [assignment: rules for the changing of attributes]
149 [assignment: access control SFP(s), information flow control SFP(s)]
150 [selection: change_default, query, modify, delete, [assignment: other operations]]
151 [assignment: list of security attributes]
152 [assignment: the authorised identified roles]
153 [assignment: access control SFP(s), information flow control SFP(s)]
154 [selection: change_default, query, modify, delete, [assignment: other operations]]
155 [assignment: list of security attributes]
156 [assignment: the authorised identified roles]
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3) Signer Key Pair Deletion SFP 157 to restrict the ability to
destruct 158 the security attribute R.SVD and
R.Signing_Key_Id as part of R.Signer 159 to authorised
Privileged User (Business Application, Operator) Signer.
160
4) Supply DTBS/R SFP 161 to restrict the ability to create 162
the security attribute R.DTBS/R as part of R.Signer 163 to
authorised Privileged User (Business Application) 164.
5) Signing SFP 165 to restrict the ability to create 166 the
security attribute R.DTBS/R as part of R.Signer 167 to
authorised Signer. 168
6) Signing SFP 169 to restrict the ability to query 170 the
security attributes as listed in FIA_USB.1 171 to authorised
Signer. 172
7) Signer Maintenance SFP 173 to restrict the ability to
change 174 the security attributes
R.Reference_Signer_Authentication_Data 175 to
authorised Privileged User (Privileged User) and Signer.
176
FMT_MSA.1/Privileged User Management of security attributes
Hierarchical to: No other components.
Dependencies: [FDP_ACC.1 Subset access control, or
FDP_IFC.1 Subset information flow control]
157 [assignment: access control SFP(s), information flow control SFP(s)]
158 [selection: change_default, query, modify, delete, [assignment: other operations]]
159 [assignment: list of security attributes]
160 [assignment: the authorised identified roles]
161 [assignment: access control SFP(s), information flow control SFP(s)]
162 [selection: change_default, query, modify, delete, [assignment: other operations]]
163 [assignment: list of security attributes]
164 [assignment: the authorised identified roles]
165 [assignment: access control SFP(s), information flow control SFP(s)]
166 [selection: change_default, query, modify, delete, [assignment: other operations]]
167 [assignment: list of security attributes]
168 [assignment: the authorised identified roles]
169 [assignment: access control SFP(s), information flow control SFP(s)]
170 [selection: change_default, query, modify, delete, [assignment: other operations]]
171 [assignment: list of security attributes]
172 [assignment: the authorised identified roles]
173 [assignment: access control SFP(s), information flow control SFP(s)]
174 [selection: change_default, query, modify, delete, [assignment: other operations]]
175 [assignment: list of security attributes]
176 [assignment: the authorised identified roles]
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FMT_SMR.1 Security roles
FMT_SMF.1 Specification of Management Functions
FMT_MSA.1.1/
Privileged User
The TSF shall enforce the: -
1) Privileged User Creation SFP 177 to restrict the ability to
create and query 178 the security attributes listed in
FIA_USB.1 for Privileged User 179 to authorised Privileged
User. 180
FMT_MSA.2 Secure security attributes
Hierarchical to: No other components.
Dependencies: [FDP_ACC.1 Subset access control, or
FDP_IFC.1 Subset information flow control]
FMT_MSA.1 Management of security attributes
FMT_SMR.1 Security roles
FMT_MSA.2.1 The TSF shall ensure that only secure values are accepted for all
security attributes listed in FIA_USB.1. 181
FMT_MSA.3/Signer Static attribute initialisation
Hierarchical to: No other components.
Dependencies: FMT_MSA.1 Management of security attributes
FMT_SMR.1 Security roles
FMT_MSA.3.1/
Signer
The TSF shall enforce the Signer Creation SFP 182 to provide
restrictive 183 default values for security attributes that are used
to enforce the SFP.
FMT_MSA.3.2/
Signer
The TSF shall allow the Privileged User (Business Application) 184
to specify alternative initial values to override the default values
when an object or information is created.
FMT_MSA.3/Privileged User Static attribute initialisation
177 [assignment: access control SFP(s), information flow control SFP(s)]
178 [selection: change_default, query, modify, delete, [assignment: other operations]]
179 [assignment: list of security attributes]
180 [assignment: the authorised identified roles]
181 [assignment: list of security attributes]
182 [assignment: access control SFP, information flow control SFP]
183 [selection, choose one of: restrictive, permissive, [assignment: other property]]
184 [assignment: the authorised identified roles]
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Hierarchical to: No other components.
Dependencies: FMT_MSA.1 Management of security attributes
FMT_SMR.1 Security roles
FMT_MSA.3.1/
Privileged User
The TSF shall enforce the Privileged User Creation SFP 185 to
provide restrictive 186 default values for security attributes that
are used to enforce the SFP.
FMT_MSA.3.2/
Privileged User
The TSF shall allow the Privileged User (Operator) 187 to specify
alternative initial values to override the default values when an
object or information is created.
FMT_MTD.1 Management of TSF data
Hierarchical to: No other components.
Dependencies: FMT_SMR.1 Security roles
FMT_SMF.1 Specification of Management Functions
FMT_MTD.1.1 The TSF shall restrict the ability to: -
1) modify 188 the R.TSF_DATA data 189 to Privileged User
(Operator). 190
Application Note 77 (Application Note 68 from [5])
The TSF data includes configuration of administrator roles.
FMT_SMF.1 Specification of Management Functions
Hierarchical to: No other components.
Dependencies: No dependencies.
FMT_SMF.1.1 The TSF shall be capable of performing the following
management functions: -
1) Signer management;
2) Privileged User management;
3) Configuration management; and
4) None. 191 192
185 [assignment: access control SFP, information flow control SFP]
186 [selection, choose one of: restrictive, permissive, [assignment: other property]]
187 [assignment: the authorised identified roles]
188 [selection: change_default, query, modify, delete, clear, [assignment: other operations]]
189 [assignment: list of TSF data]
190 [assignment: the authorised identified roles]
191 [assignment: additional list of management functions to be provided by the TSF]
192 [assignment: list of management functions to be provided by the TSF]
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FMT_SMR.2 Restrictions on security roles
Hierarchical to: FMT_SMR.1 Security roles
Dependencies: FIA_UTD.1 Timing of identification
FMT_SMR.2.1 The TSF shall maintain the roles: Signer and Privileged User
(Operator and Business Application)193, none. 194
FMT_SMR.2.2 The TSF shall be able to associate users with roles.
FMT_SMR.2.3 The TSF shall ensure that the conditions Signer can’t be a
Privileged User are satisfied.
Application Note 78 (Application Note 69 from [5], refined by ST author)
Applied. The ST writer described which roles are defined in the TOE and which operations
the role can perform.
6.4.6 Protection of the TSF (FPT)
FPT_PHP.1 Passive detection of physical attack
Hierarchical to: No other components.
Dependencies: No dependencies.
FPT_PHP.1.1 The TSF shall provide unambiguous detection of physical
tampering that might compromise the TSF.
FPT_PHP.1.2 The TSF shall provide the capability to determine whether
physical tampering with the TSF's devices or TSF's elements has
occurred.
Application Note 79 (Application Note 70 from [5])
Passive detection of a physical attack is typically achieved by using physical seals and an
appropriate physical design of the TOE that allows the TOE administrator to verify the
physical integrity of the TOE as part of a routine inspection procedure.
Because of the requirement for a physically secure environment with regular inspections
(cf. OE.ENV), the level of protection (and hence resistance to attack potential) that is
required by the implementation of FPT_PHP.1 for this TOE is equivalent to the physical
security mechanisms for tamper detection and response required by section 7.7.2 Physical
security general requirements and section 7.7.3 Physical security requirements for each
physical security embodiment in ISO/IEC 19790 [22] for Security Level 3.
FPT_PHP.3 Resistance to physical attack
Hierarchical to: No other components.
193 [assignment: authorised identified roles]
194 [assignment: other authorised identified roles]
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Dependencies: No dependencies.
FPT_PHP.3.1 TSF shall resist opening the case 195 to the cover 196 by responding
automatically such that the SFRs are always enforced.
Application Note 80 (Application Note 69 from [5], refined by ST author)
Applied. The TOE is not implemented as a local application with the same physical
boundary as the CM. To make it more clear: the CM has its own tamper protection but the
TOE is not implemented inside the CM. Both the CM and the TOE are put inside an
appliance and the appliances protection is responsible for the protection of the TOE. If the
appliance detects tamper it notifies and starts the CMs tamper protection procedures as
well.
Application Note 81 (Application Note 70 from [5])
This SFR is linked to the requirements for passive detection of physical attacks in
FPT_PHP.1, and should identify the relevant responses of the TOE involved in meeting the
key zeroisation requirements of ISO/IEC 19790 [22] Security Level 3. As in the case of
FPT_PHP.1, because of the requirement for a physically secure environment with regular
inspections (cf. OE.ENV), the level of protection (and hence resistance to attack potential)
that is required by the implementation of FPT_PHP.3 for this TOE is equivalent to the level
of assessment for this aspect of tamper detection and response required for section 7.7.2
Physical security general requirements and section 7.7.3 Physical security requirements by
each physical security embodiment in ISO/IEC 19790 [22] for Security Level 3.
FPT_RPL.1 Replay detection
Hierarchical to: No other components.
Dependencies: No dependencies.
FPT_RPL.1.1 The TSF shall detect replay for the following entities: R.SAD. 197
FPT_RPL.1.2 The TSF shall perform reject the signature operation 198 when
replay is detected.
FPT_STM.1 Reliable time stamps
Hierarchical to: No other components.
Dependencies: No dependencies.
FPT_STM.1.1 The TSF shall be able to provide reliable time stamps.
Application Note 82 (Application Note 71 from [5], refined by the ST Author)
The system clock is the time source. One or more NTP Servers can be configured in TOE to
ensure its system clock is synched with a trusted clock. In case of time deviation is detected
195 [assignment: physical tampering scenarios]
196 [assignment: list of TSF devices/elements]
197 [assignment: list of identified entities]
198 [assignment: list of specific actions]
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by TOE, it automatically notifies and suspends its operations, i.e. Signer creation, signature
creation, etc.
FPT_TDC.1 Inter-TSF basic TSF data consistency
Hierarchical to: No other components.
Dependencies: No dependencies.
FPT_TDC.1.1 The TSF shall provide the capability to consistently interpret: -
1) R.Signer;
2) R.Reference_Signer_Authentication_Data;
3) R.SAD;
4) R.DTBS/R;
5) R.SVD;
6) R.Privileged_User; and
7) R.Reference_Privileged_User_Authentication_Data
8) R.TSF_DATA. 199
when shared between the TSF and another trusted IT product.
FPT_TDC.1.2 The TSF shall use data integrity either on data or on
communication channel 200 when interpreting the TSF data from
another trusted IT product.
Application Note 83 (Application Note 72 from [5], refined by ST author)
Applied. The SFR is used to handle the situation where the whole or part of the above data
are stored outside the TOE.
6.4.7 Trusted Paths/Channels (FTP)
FTP_TRP.1/SSA Trusted path
Hierarchical to: No other components.
Dependencies: No dependencies.
FTP_TRP.1.1/
SSA
The TSF shall provide a communication path between itself and:
Privileged User (Operator and Business Application) through
SSA 201
199 [assignment: list of TSF data types]
200 [assignment: list of interpretation rules to be applied by the TSF]
201 [selection: remote, local]
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users that is logically distinct from other communication paths
and provides assured identification of its end points and
protection of the communicated data from modification. 202
FTP_TRP.1.2/
SSA
The TSF shall permit: Privileged User (Operator and Business
Application) through SSA. 203
to initiate communication via the trusted path.
FTP_TRP.1.3/
SSA
The TSF shall require the use of the trusted path for: -
1) FDP_ACC.1.1/Privileged User Creation;
2) FDP_ACC.1/Signer Creation;
3) FDP_ACC.1/Signer Maintenance;
4) FDP_ACC.1/Signer Key Pair Generation;
5) FDP_ACC.1/Signer Key Pair Deletion;
6) FDP_ACC.1/Supply DTBS/R;
7) FDP_ACC.1/TOE Maintenance;
8) None. 204 205
Application Note 84 (Application Note 73 from [5])
Since it is not all data transmitted to the TOE that needs to be protected in confidentiality,
FTP_TRP.1/SSA only requires protection from modification.
FTP_TRP.1/SIC Trusted path
Hierarchical to: No other components.
Dependencies: No dependencies.
FTP_TRP.1.1/
SIC
The TSF shall provide a communication path between itself and:
Remote Signer through the SIC 206
users that is logically distinct from other communication paths
and provides assured identification of its end points and
protection of the communicated data from modification. 207
FTP_TRP.1.2/
SIC
The TSF shall permit: Remote Signer through the SIC 208
to initiate communication via the trusted path.
FTP_TRP.1.3/
SIC
The TSF shall require the use of the trusted path for
1) FDP_ACC.1/Signer Maintenance
2) FDP_ACC.1/Signer Key Pair Generation
202 [selection: modification, disclosure, [assignment: other services for which trusted path is required]]
203 [selection: the TSF, local users, remote users]
204 [assignment: other services for which trusted path is required]
205 [selection: initial user authentication, [assignment: other services for which trusted path is required]]
206 [selection: remote, local]
207 [selection: modification, disclosure, [assignment: other services for which trusted path is required]]
208 [selection: the TSF, local users, remote users]
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3) FDP_ACC.1/Signer Key Pair Deletion
4) FDP_ACC.1/Signing
5) None 209 210
Application Note 85 (Application Note 74 from [5], refined by ST author)
Since it is not all data transmitted to the TOE that needs to be protected in confidentiality,
FTP_TRP.1.1/SIC only requires protection from modification. The ST writer shall describe
if the SAP can be used to transmit sensitive data and how these are protected in
confidentiality.
The TOE is not expected to verify the SIC as a communication end-point and it may rely on
the Signer authentication.
Application Note 86 (from ST Author)
The communication path is the following: SIC – SAP – SSA – TOE. From the SIC the
communication is done over TLS 1.2 authenticated channel.
FTP_ITC.1/CM Inter-TSF trusted channel
Hierarchical to: No other components.
Dependencies: No dependencies.
FTP_ITC.1.1/
CM
The TSF shall provide a communication path between itself and a
CM certified according to EN 419 221-5 [7] that is logically
distinct from other communication paths and provides assured
authentication of its end points and protection of the
communicated data from modification or disclosure.
FTP_ITC.1.2/
CM
The TSF shall permit the TSF and a CM certified according to EN
419 221-5 [7] 211 to initiate communication via the trusted
channel.
FTP_ITC.1.3/
CM
The TSF shall initiate communication via the trusted channel for
all functions which need a CM. 212
Application Note 87 (Application Note 75 from [5], refined by ST author)
Applied. Communication with the CM is through a secure channel using vendor specific
APIs commands in any case.
209 [assignment: other services for which trusted path is required]
210 [selection: initial user authentication, [assignment: other services for which trusted path is required]]
211 [selection: the TSF, another trusted IT product]
212 [assignment: list of functions for which a trusted channel is required]
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6.5 Security Requirements Rationale
6.5.1 Security Requirements Coverage
The following table is used to demonstrate that every SFR is used to cover an objective
and that every objective is covered by an SFR.
OT.SIGNER_PROTECTION
OT.REFERENCE_SIGNER_AUTHENTICATION_DATA
OT.SIGNER_KEY_PAIR_GENERATION
OT.SVD
OT.PRIVILEGED_USER_MANAGEMENT
OT.PRIVILEGED_USER_AUTHENTICATION
OT.PRIVILEGED_USER_PROTECTION
OT.SIGNER_MANAGEMENT
OT.SYSTEM_PROTECTION
OT.AUDIT_PROTECTION
OT.SAD_VERIFICATION
OT.SAP
OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION
OT.DTBSR_INTEGRITY
OT.SIGNATURE_INTEGRITY
OT.CRYPTO
OT.RANDOM
Security Audit
FAU_GEN.1 X
FAU_GEN.2 X
Cryptographic
Support
FCS_CKM.1/RSA X X
FCS_CKM.1/ECDSA X X
FCS_CKM.1/AES X X
FCS_CKM.4 X
FCS_COP.1/
DIG_SIG_GEN
X X X
FCS_COP.1
/DIG_SIG_VER
X X X
FCS_COP.1/HASH X X X
FCS_COP.1/HMAC X X X
FCS_COP.1/ENC X X X
FCS_RNG.1 X X
User Data
Protection
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OT.SIGNER_PROTECTION
OT.REFERENCE_SIGNER_AUTHENTICATION_DATA
OT.SIGNER_KEY_PAIR_GENERATION
OT.SVD
OT.PRIVILEGED_USER_MANAGEMENT
OT.PRIVILEGED_USER_AUTHENTICATION
OT.PRIVILEGED_USER_PROTECTION
OT.SIGNER_MANAGEMENT
OT.SYSTEM_PROTECTION
OT.AUDIT_PROTECTION
OT.SAD_VERIFICATION
OT.SAP
OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION
OT.DTBSR_INTEGRITY
OT.SIGNATURE_INTEGRITY
OT.CRYPTO
OT.RANDOM
FDP_ACC.1/Privileg
ed User Creation
X
FDP_ACF.1/Privileg
ed User Creation
X
FDP_ACC.1/Signer
Creation
X X
FDP_ACF.1/Signer
Creation
X X
FDP_ACF.1/Signer
Maintenance
X
FDP_ACC.1/Signer
Maintenance
X
FDP_ACC.1/Signer
Key Pair Generation
X X
FDP_ACF.1/Signer
Key Pair Generation
X X
FDP_ACC.1/Signer
Key Pair Deletion
X
FDP_ACF.1/Signer
Key Pair Deletion
X
FDP_ACC.1/Supply
DTBS/R
X
FDP_ACF.1/Supply
DTBS/R
X
FDP_ACC.1/Signing X X
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OT.SIGNER_PROTECTION
OT.REFERENCE_SIGNER_AUTHENTICATION_DATA
OT.SIGNER_KEY_PAIR_GENERATION
OT.SVD
OT.PRIVILEGED_USER_MANAGEMENT
OT.PRIVILEGED_USER_AUTHENTICATION
OT.PRIVILEGED_USER_PROTECTION
OT.SIGNER_MANAGEMENT
OT.SYSTEM_PROTECTION
OT.AUDIT_PROTECTION
OT.SAD_VERIFICATION
OT.SAP
OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION
OT.DTBSR_INTEGRITY
OT.SIGNATURE_INTEGRITY
OT.CRYPTO
OT.RANDOM
FDP_ACF.1/Signing X X
FDP_ACC.1/TOE
Maintenance
X
FDP_ACF.1/TOE
Maintenance
X
FDP_ETC.2/Signer X
FDP_IFC.1/Signer X
FDP_IFF.1/Signer X
FDP_ETC.2/Privileg
ed User
X X
FDP_IFC.1/Privilege
d User
X X
FDP_IFF.1/Privilege
d User
X X
FDP_ITC.2/Signer X
FDP_ITC.2/Privilege
d User
X X
FDP_UCT.1 X
FDP_UIT.1 X
Identification and
Authentication
FIA_AFL.1/BA X X
FIA_AFL.1/Signer X
FIA_ATD.1 X X X
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OT.SIGNER_PROTECTION
OT.REFERENCE_SIGNER_AUTHENTICATION_DATA
OT.SIGNER_KEY_PAIR_GENERATION
OT.SVD
OT.PRIVILEGED_USER_MANAGEMENT
OT.PRIVILEGED_USER_AUTHENTICATION
OT.PRIVILEGED_USER_PROTECTION
OT.SIGNER_MANAGEMENT
OT.SYSTEM_PROTECTION
OT.AUDIT_PROTECTION
OT.SAD_VERIFICATION
OT.SAP
OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION
OT.DTBSR_INTEGRITY
OT.SIGNATURE_INTEGRITY
OT.CRYPTO
OT.RANDOM
FIA_UAU.1 X X
FIA_UAU.5/Signer X
FIA_UAU.5/Privileg
ed User
X
FIA_UID.2 X X X
FIA_USB.1 X X X X
Security
Management
FMT_MSA.1/Signer X
FMT_MSA.1/Privile
ged User
X X
FMT_MSA.2 X X
FMT_MSA.3/Signer X
FMT_MSA.3/Privile
ged User
X X
FMT_MTD.1 X
FMT_SMF.1 X
FMT_SMR.2 X
Protection of the
TSF
FPT_PHP.1 X
FPT_PHP.3 X
FPT_RPL.1 X
FPT_STM.1 X
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OT.SIGNER_PROTECTION
OT.REFERENCE_SIGNER_AUTHENTICATION_DATA
OT.SIGNER_KEY_PAIR_GENERATION
OT.SVD
OT.PRIVILEGED_USER_MANAGEMENT
OT.PRIVILEGED_USER_AUTHENTICATION
OT.PRIVILEGED_USER_PROTECTION
OT.SIGNER_MANAGEMENT
OT.SYSTEM_PROTECTION
OT.AUDIT_PROTECTION
OT.SAD_VERIFICATION
OT.SAP
OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION
OT.DTBSR_INTEGRITY
OT.SIGNATURE_INTEGRITY
OT.CRYPTO
OT.RANDOM
FPT_TDC.1 X X
Trusted
Path/Channels
FTP_TRP.1/SSA X X
FTP_TRP.1/SIC X X X
FTP_ITC.1/CM X X
Table 6-6: Security requirements coverage
OT.SIGNER_PROTECTION is handled by requirements export and import of R.Signer in a
secure way. (FDP_ETC.2/Signer, FDP_IFC.1/Signer, FDP_IFF.1/Signer, FDP_ITC.2/Signer,
FDP_UCT.1 FDP_UIT.1 and FPT_TDC.1). The actual description of the data is described in
FIA_ATD.1 and FIA_USB.1.
OT.REFERENCE_SIGNER AUTHENTICATION_DATA is handled by FDP_ACC.1/Signer
Creation, FDP_ACF.1/Signer Creation, FDP_ACC.1/Signer Maintenance and
FDP_ACF.1/Signer Maintenance, which describes access control for creating and updating
R.Signer and R.Reference_Signer_Authentication_Data.
OT.SIGNER_KEY_PAIR_GENERATION is handled by the requirements for key generation
and cryptographic algorithms in FCS_CKM.1/RSA, FCS_CKM.1/ECDSA, FCS_CKM.1/AES,
FCS_COP.1/DIG_SIG_GEN, FCS_COP.1/DIG_SIG_VER, FCS_COP.1/HASH,
FCS_COP.1/HMAC, FCS_COP.1/ENC. FCS_RNG.1 provides a random source for key
generation. FCS_CKM.4 describes the requirements for key destruction. FDP_ACC.1/Signer
Key Pair Generation and FDP ACF.1/Signer Key Pair Generation describes access control
for creating a key pair. FIA_USB.1 describes that R.Signing_Key_Id is associated with
Signer. FTP_ITC.1/CM can be used to communicate securely with a CM.
OT.SVD is handled by the requirements in FDP_ACC.1/Signer Key Pair Generation and
FDP_ACF.1/Signer Key Pair Generation.
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OT.PRIVILEGED_USER_MANAGEMENT is handled by requirements for export and import
of R.Privileged User in a secure way (FDP_ETC.2/Privileged User, FDP_IFC.1/Privileged
User, FDP_IFF.1/Privileged User, FDP_ITC.2/Privileged User and FPT_TDC.1). The actual
description of the data is described in FIA_ATD.1 and FIA_USB.1. Authentication of
Privileged User is handled by FIA_UID.2, FMT_MSA.1/Privileged User, FMT_MSA.2 and
FMT_MSA.3/Privileged User. FDP_ACC.1/Privileged User Creation and
FDP_ACF.1/Privileged User Creation describes access controls for creating Privileged
Users.
OT.PRIVILEGED_USER_AUTHENTICATION is handled by FIA_AFL.1/BA, FIA_UAU.1 and
FIA_UAU.5/Privileged User.
OT.PRIVILEGED_USER_PROTECTION is handled by requirements export and import of
Privileged User in a secure way. FDP_ETC.2/Privileged User, FDP_IFC.1/Privileged User,
FDP_IFF.1/Privileged User, FDP_ITC.2/Privileged User, FIA_UID.2. The actual description of the
data is described in FIA_ATD.1 and FIA_USB.1
OT.SIGNER_MANAGEMENT is handled by the requirements for access control in
FDP_ACC.1/Signer Creation, FDP_ACF.1/Signer Creation, FDP_ACC.1/Signer Key Pair
Deletionand FDP_ACF.1/Signer Key Pair Deletion. Authentication of Signers and Privileged
Users are handled by FIA_UID.2, FMT_MSA.1/Signer, FMT_MSA.1/Privileged User,
FMT_MSA.2, FMT_MSA.3/Signer and FMT_MSA.3/Privileged User.
OT.SYSTEM_PROTECTION is handled by FMT_MTD.1, FMT_SMF.1 and FMT_SMR.2.
FDP_ACC.1/TOE Maintenance and FDP_ACF.1/TOE Maintenance describes access control
rules for managing TSF data. FPT_PHP.1 and FPT_PHP.3 describes requirements for TSF
protection. FTP_TRP.1/SSA describes that only a Privileged User can maintain a TOE.
OT.AUDIT_PROTECTION is handled by the requirements for audit record generation
FAU_GEN.1 and FAU_GEN.2 using reliable time stamps in FPT_STM.1.
OT.SAD_VERIFICATION is handled by the FIA_AFL.1/BA, FIA_AFL.1/Signer, FIA_UAU.1 and
FIA_UAU.5/Signer. FDP_ACC.1/Signing and FDP_ACF.1/Signing describes access control
rules for the signature operation and well as for SAP verification.
OT.SAP is covered by the requirements FTP_TRP.1/SIC and FPT_RPL.1 the protocol
between the SIC and TSF.
OT.SIGNATURE_AUTHENTICATION_DATA_PROTECTION is covered by FTP_TRP.1/SIC,
which describes the requirements for data transmitted to the TOE, is protected in integrity.
OT.DTBSR_INTEGRITY is covered by FT_TRP.1/SSA and FTP_TRP.1/SIC requiring data
transmission to be protected in integrity. Also covered by access control rules
FDP_ACC.1/Supply DTBS/R and FDP_ACF.1/Supply DTBS/R for transmitting DTBS/R to the
TSF.
OT.SIGNATURE_INTEGRITY is handled by FCS_COP.1/DIG_SIG_GEN,
FCS_COP.1/DIG_SIG_VER, FCS_COP.1/HASH, FCS_COP.1/HMAC, FCS_COP.1/ENC, which
describes requirements for algorithms. FTP_ITC.1/CM may be used to transmit data
securely between the TOE and the CM. Access control for the signature operation is
ensured by FDP_ACC.1/Signing and FDP_ACF.1/Signing.
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OT.CRYPTO is covered by FCS_CKM.1/RSA, FCS_CKM.1/ECDSA, FCS_CKM.1/AES,
FCS_COP.1/DIG_SIG_GEN, FCS_COP.1/DIG_SIG_VER, FCS_COP.1/HASH,
FCS_COP.1/HMAC, FCS_COP.1/ENC, which describes requirements for key generation and
algorithms.
OT.RANDOM is handled by FCS_RNG.1, which describes requirement on the random
number generation.
6.6 SFR Dependencies
The dependencies between SFRs are addressed as shown in.
Requirement Dependencies Fulfilled by
FAU_GEN.1 FPT_STM.1 FPT_STM.1
FAU_GEN.2 FAU_GEN.1
FIA_UID.1
FAU_GEN.1
FIA_UID.2
FCS_CKM.1/RSA [FCS_CKM.2 or FCS_COP.1]
FCS_CKM.4
FCS_COP.1/DIG_SIG_GEN,
FCS_COP.1/DIG_SIG_VER,
FCS_COP.1/HASH and FCS_CKM.4
FCS_CKM.1/ECDSA [FCS_CKM.2 or FCS_COP.1]
FCS_CKM.4
FCS_COP.1/DIG_SIG_GEN,
FCS_COP.1/DIG_SIG_VER,
FCS_COP.1/HASH and FCS_CKM.4
FCS_CKM.1/AES [FCS_CKM.2 or FCS_COP.1]
FCS_CKM.4
FCS_COP.1/DIG_SIG_GEN,
FCS_COP.1/DIG_SIG_VER,
FCS_COP.1/HASH and FCS_CKM.4
FCS_CKM.4 [FDP_ITC.1 or FDP_ITC.2 or
FCS_CKM.1]
FCS_CKM.1/*
FCS_COP.1/DIG_SIG_GEN [FDP_ITC.1 or FDP_ITC.2 or
FCS_CKM.1]
FCS_CKM.4
FCS_CKM.1/RSA,
FCS_CKM.1/ECDSA and
FCS_CKM.4
FCS_COP.1/DIG_SIG_VER [FDP_ITC.1 or FDP_ITC.2 or
FCS_CKM.1]
FCS_CKM.4
FCS_CKM.1/RSA,
FCS_CKM.1/ECDSA and
FCS_CKM.4
FCS_COP.1/HASH [FDP_ITC.1 or FDP_ITC.2 or
FCS_CKM.1]
FCS_CKM.4
FCS_CKM.1/RSA,
FCS_CKM.1/ECDSA and
FCS_CKM.4
FCS_COP.1/HMAC [FDP_ITC.1 or FDP_ITC.2 or
FCS_CKM.1]
FCS_CKM.4
FCS_CKM.1/RSA,
FCS_CKM.1/ECDSA and
FCS_CKM.4
FCS_COP.1/ENC [FDP_ITC.1 or FDP_ITC.2 or
FCS_CKM.1]
FCS_CKM.4
FCS_CKM.1/AES and FCS_CKM.4
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Requirement Dependencies Fulfilled by
FCS_RNG.1 None No dependents
FDP_ACC.1/Privileged User
Creation
FDP_ACF.1 FDP_ACF.1/Privileged User
Creation
FDP_ACC.1/Signer Creation FDP_ACF.1 FDP_ACF.1/Signer Creation
FDP_ACC.1/Signer Key Pair
Generation
FDP_ACF.1 FDP_ACF.1/Signer Key Pair
Generation
FDP_ACC.1/Signer Maintenance FDP_ACF.1 FDP_ACF.1/Signer Maintenance
FDP_ACC.1/Signer Key Pair
Deletion
FDP_ACF.1 FDP_ACF.1/Signer Key Pair
Deletion
FDP_ACC.1/Supply DTBS/R FDP_ACF.1 FDP_ACF.1/Supply DTBS/R
FDP_ACC.1/Signing FDP_ACF.1 FDP_ACF.1/Signing
FDP_ACC.1/TOE Maintenance FDP_ACF.1 FDP_ACF.1/TOE Maintenance
FDP_ACF.1/Privileged User
Creation
FDP_ACC.1
FMT_MSA.3
FDP_ACC.1/Privileged User
Creation
FMT_MSA.3/Privileged User
FDP_ACF.1/Signer Creation FDP_ACC.1
FMT_MSA.3
FDP_ACC.1/Signer Creation
FMT_MSA.3/Signer
FDP_ACF.1/Signer Key Pair
Generation
FDP_ACC.1
FMT_MSA.3
FDP_ACC.1/Signer Key Pair
Generation
FMT_MSA.3/Signer
FDP_ACF.1/Signer Maintenance FDP_ACC.1
FMT_MSA.3
FDP_ACC.1/Signer Maintenance
FMT_MSA.3/Signer
FDP_ACF.1/Signer Key Pair
Deletion
FDP_ACC.1
FMT_MSA.3
FDP_ACC.1/Signer Key Pair
Deletion
FMT_MSA.3/Signer
FDP_ACF.1/Supply DTBS/R FDP_ACC.1
FMT_MSA.3
FDP_ACC.1/Supply DTBS/R
FMT_MSA.3/Signer
FDP_ACF.1/Signing FDP_ACC.1
FMT_MSA.3
FDP_ACC.1/Signing
FMT_MSA.3/Signer
FDP_ACF.1/TOE Maintenance FDP_ACC.1
FMT_MSA.3
FDP_ACC.1/TOE Maintenance
FMT_MSA.3/Privileged User
FDP_ETC.2/Signer [FDP_ACC.1 or
FDP_IFC.1]
FDP_IFC.1/Signer
FDP_ETC.2/Privileged User [FDP_ACC.1 or
FDP_IFC.1]
FDP_IFC.1/Privileged User
FDP_IFC.1/Signer FDP_IFF.1 FDP_IFF.1/Signer
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Requirement Dependencies Fulfilled by
FDP_IFF.1/Signer FDP_IFC.1
FMT_MSA.3
FDP_IFC.1/Signer
FMT_MSA.3/Signer
FDP_IFC.1/Privileged User FDP_IFF.1 FDP_IFF.1/Privileged User
FDP_IFF.1/Privileged User FDP_IFC.1
FMT_MSA.3
FDP_IFC.1/Privileged User
FMT_MSA.3/Privileged User
FDP_ITC.2/Signer [FDP_ACC.1 or FDP_IFC.1]
[FTP_ITC.1 or FTP_TRP.1]
FTP_TDC.1
FDP_IFC.1/Signer
FTP_TRP.1/SSA and
FTP_TRP.1/SIC
FPT_TDC.1
FDP_ITC.2/Privileged User [FDP_ACC.1 or FDP_IFC.1]
[FTP_ITC.1 or FTP_TRP.1]
FTP_TDC.1
FDP_IFC.1/Privileged User
FTP_TRP.1/SSA
FPT_TDC.1
FDP_UCT.1 [FTP_ITC.1 or FTP_TRP.1]
[FDP_ACC.1 or FDP_IFC.1]
FTP_TRP.1/SSA and
FTP_TRP.1/SIC
FDP_IFC.1/Signer
FDP_IFC.1/Privileged User
FDP_UIT.1 [FDP_ACC.1 or FDP_IFC.1]
[FTP_ITC.1 or FTP_TRP.1]
FDP_IFC.1/Signer
FDP_IFC.1/Privileged User
FTP_TRP.1/SSA and
FTP_TRP.1/SIC
FIA_AFL.1/BA FIA_UAU.1 FIA_UAU.1
FIA_AFL.1/Signer FIA_UAU.1 FIA_UAU.1
FIA_ATD.1 None No dependents
FIA_UAU.1 FIA_UID.1 FIA_UID.2
FIA_UAU.5/Signer None No dependents
FIA_UAU.5/Privileged User None No dependents
FIA_UID.2 None No dependents
FIA_USB.1 FIA_ATD.1 FIA_ATD.1
FMT_MSA.1/Signer [FDP_ACC.1 or FDP_IFC.1]
FMT_SMR.1
FMT_SMF.1
FDP_IFC.1/Signer
FMT_SMR.2
FMT_SMF.1
FMT_MSA.1/Privileged User [FDP_ACC.1 or FDP_IFC.1]
FMT_SMR.1
FMT_SMF.1
FDP_IFC.1/Privileged User
FMT_SMR.2
FMT_SMF.1
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Requirement Dependencies Fulfilled by
FMT_MSA.2 [FDP_ACC.1 or FDP_IFC.1]
FMT_MSA.1
FMT_SMR.1
FDP_IFC.1/Signer
FDP_IFC.1/Privileged User
FMT_MSA.1/Signer
FMT_MSA.1/Privileged User
FMT_SMR.2
FMT_MSA.3/Signer FMT_MSA.1
FMT_SMR.1
FMT_MSA.1/Signer
FMT_SMR.2
FMT_MSA.3/Privileged User FMT_MSA.1
FMT_SMR.1
FMT_MSA.1/Privileged
FMT_SMR.2
FMT_MTD.1 FMT_SMR.1
FMT_SMF.1
FMT_SMR.2
FMT_SMF.1
FMT_SMF.1 None No dependents
FMT_SMR.2 FIA_UID.1 FIA_UID.2
FPT_PHP.1 None No dependents
FPT_PHP.3 None No dependents
FPT_RPL.1 None No dependents
FPT_STM.1 None No dependents
FPT_TDC.1 None No dependents
FTP_TRP.1/SSA None No dependents
FTP_TRP.1/SIC None No dependents
FTP_ITC.1/CM None No dependents
Table 6-7: Dependencies
6.7 Security Assurance Requirements
The security assurance requirement level is EAL 4 augmented with AVA_VAN.5. The
assurance components are identified in the table below with the augmented item in bold.
Since the TOE is operated in a physically protected environment as described in OE.ENV
an evaluation against this ST will probably not include physical attacks.
Assurance Class Assurance components
ADV: Development
ADV_ARC.1 Security architecture description
ADV_FSP.4 Complete functional specifications
ADV_IMP.1 Implementation representation of the TSF
ADV_TDS.3 Basic modular design
AGD: Guidance documents
AGD_OPE.1 Operational user guidance
AGD_PRE.1 Preparative procedures
ALC: Life-cycle support
ALC_CMC.4 Production support, acceptance procedures and
automation
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Assurance Class Assurance components
ALC_CMS.4 Problem tracking CM coverage
ALC_DEL.1 Delivery procedures
ALC_DVS.1 Identification of security measures
ALC_LCD.1 Developer defined life-cycle model
ALC_TAT.1 Well-defined development tools
ASE: Security Target evaluation
ASE_INT.1 ST introduction
ASE_CCL.1 Conformance claims
ASE_SPD.1 Security problem definition
ASE_OBJ.2 Security objectives
ASE_ECD.1 Extended components definition
ASE_REQ.2 Derived security requirements
ASE_TSS.1 TOE summary specification
ATE: Tests
ATE_COV.2 Analysis of coverage
ATE_DPT.1 Testing: basic design
ATE_FUN.1 Functional testing
ATE_IND.2 Independent testing - sample
AVA: Vulnerability assessment AVA_VAN.5 Advanced methodical vulnerability analysis
Table 6-8 Security Assurance Requirements: EAL 4 augmented with AVA_VAN.5
EAL 4 permits a developer to gain maximum assurance from positive security engineering
based on good commercial development practises which, through rigorous, do not require
substantial specialist knowledge, skills, and other resources. EAL 4 is the highest level at
which it is likely to be economically feasible to retrofit to an existing product line.
As the TOE manages SCD generation and authorises its use, it manages security attributes
which can only be ensured by the TOE. While the TOE is assumed to be in a physically
protected environment, it is still subject to logical remote attacks and should be evaluated
to deal with High attack potential.
EAL 4 is therefore augmented with AVA_VAN.5.
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7. TOE Summary Specification
To fulfil the Security Functional Requirements, the TOE comprises the following Security
Functions (TSF): -
1. User Roles and Authentication (TSF_AUTH);
2. Key Security (TSF_CRYPTO);
3. Access and information flow control (TSF_CTRL);
4. Data protection (TSF_DP);
5. Audit (TSF_AUDIT); and
6. Communication protection (TSF_COMM).
Each of the TOE security functions is described in the following sections in detail.
7.1 TOE Security Functions
7.1.1 User Roles & Authentication (TSF_AUTH)
#FMT_SMR.2 Restrictions on security roles
The TOE maintains Privileged User (Operator or Business Application) and Unprivileged User
(Signer) roles and associates users with roles. The TOE identifies users by means of a unique
user identifier. The TOE ensures that each user has only one role, consequently a Signer can’t
be a Privileged User. These users are stored and maintained in different subsystems and
identified with different IDs (Operator ID, Client ID, User ID).
All the Operators and Business Application configurations are stored in Ascertia ADSS Server
SAM database. The integrity of the records stored in Ascertia ADSS Server SAM database is
protected by sequenced HMAC. The HMAC secret key is stored in the CM.
#FIA_UAU.5/Privileged User Multiple authentication mechanisms
Privileged Users authenticate via TLS channel to the TOE. Business Application authenticates
with its clientId and certificate. Operator authenticates himself with his certificate stored on
a PIN protected card.
#FIA_UID.2 User identification before any action
#FIA_UAU.1 Timing of authentication
The Signer’s registered mobile device holds an authorization key pair in the phone’s secure
element. The key pair is created during the device registration process with the help of two
OTPs. Signers must identify and authenticate themselves using two OTPs (sent on registered
mobile number and email) i.e. Login to the Go>Sign Mobile app before doing anything to the
TOE.
#FIA_UAU.5/Signer Multiple authentication mechanisms
Fingerprint authentication is used inside the Go>Sign Mobile app (if the Signer is already
logged in) to authorize a signing request, i.e. create the SAD.
#FIA_AFL.1 Authentication failure handling
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The TOE handles authentication failures in a separate way for each role.
Privileged User (Ascertia ADSS Server SAM Operator): Operator’s TLS client authentication
key/certificate should be held on a smartcard/token. At the time of login using TLS client
certificate authentication mechanism, the first check is the PIN/password entry for the release
of the TLS client private key. If this check fails then it is possible for the smart card/token to
be locked, e.g. after three incorrect attempts.
Privileged User (Business Application): If a business application fails to authenticate, e.g.
using a wrong TLS client certificate to connect then Ascertia ADSS Server SAM marks the
business application as inactive and an Ascertia ADSS Server SAM Operator is then required
to activate it.
Signer: Signer login retries limit and blockage interval after performing number of retries are
defined in SAM Advanced Settings.
#FIA_ATD.1 User attribute definition
#FIA_USB.1 User-subject binding
#FMT_MSA.2
The TOE maintains accounts (with different security attributes) belonging to individual users.
TOE validates the values assigned for these attributes.
7.1.2 Key Security (TSF_CRYPTO)
#FCS_CKM.1
#FCS_CKM.4
#FCS_COP.1
#FCS_RNG.1
The TOE calls with appropriate parameters a CM certified in conformance with EN 419 221-5
[7] for any key management or cryptographic operations, random number generation.
7.1.3 Access and information flow control (TSF_CTRL)
#FDP_ACC.1/Privileged User Creation
#FDP_ACF.1/Privileged User Creation
#FMT_MSA.1/Privileged User
#FMT_MSA.3/Privileged User
#FMT_SMF.1
When Ascertia ADSS Server SAM is installed, a default Ascertia ADSS Server SAM Operator
account is automatically created with a default Operator’s certificate. The default operator
logs in to the Ascertia ADSS Server SAM Admin Console and creates Privileged Users, i.e.
Ascertia ADSS Server SAM Operators and Client Applications. When Operator logs in to
Ascertia ADSS Server SAM Admin Console using the default operator’s certificate, then a
warning dialog is shown to the Operator to instruct how to change the default certificate with
new Operator certificate. If Operator doesn’t setup new Operator certificate within 7 (seven)
days, then operator access to Ascertia ADSS Server SAM Admin Console is blocked and
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complete reinstallation of Ascertia ADSS Server SAM would be required. Only Operators can
manage Privileged Users after successful authentication.
#FDP_ACC.1/Signer Creation
#FDP_ACF.1/Signer Creation
#FMT_MSA.1/Signer
#FMT_MSA.3/Signer
#FMT_MSA.2
#FMT_SMF.1
The TOE guarantees that only a Business Application as a Privileged User can create new Signer
and initiate key pair generation on behalf of the Signer. A typical Signer registration process
involves registering Signer details and generating remote signing key pair and digital
certificate. The Signer visits a Business Application web page and provides their registration
details for the Business Application. The registration details include: -
 User Name (full name of the Signer);
 User ID (a unique identifier for the Signer);
 Password (optionally used to authenticate the Signer in the Business Application at the
time of signing if provided);
 Email Address (used for subsequent communication purposes and to send the OTP
during mobile device registration); and
 Mobile Number (to send the OTP during mobile device registration).
The Business Application receives the registration details from the Signer and creates a user
registration request for RAS Service. The Business Application includes Application ID (clientId)
in the registration request for RAS Service. The RAS Service internally requests the TOE to store
the Signer registration details. The TOE maintains and validates all the Signer registration and
security data in Ascertia ADSS Server SAM database. In a different scenario, the Signer may be
registered by a RA officer where Signer details are entered in the system by RA officer after
manually verifying the Signer’s identity. In both cases, i.e. whether the Signer is directly
registering with the business application or RA officer registers the user, the RAS Service would
require same details about the Signer.
#FDP_ACC.1/Signer Key Pair Generation
#FDP_ACF.1/Signer Key Pair Generation
#FDP_IFC.1/Signer
#FDP_IFF.1/Signer
Once the Signer details are registered, the Business Application requests the ADSS RAS Service
to generate the signing key pair for the Signer. The TOE does not use pre-generated keys. To
generate a signing key pair for a registered Signer, the Business Application creates a request
for RAS Service which then forwards the request to SAM. The request includes: -
 User ID (a unique identifier for the Signer).
 Key ID (a unique ID for the signing key pair).
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 Subject DN (the Subject DN to be used in the CSR).
 SAM Profile ID (SAM Profile defines the key type, e.g. RSA or ECDSA, key length, e.g.
2048, Signature Padding Scheme, etc.).
The RAS Service requests the SAM to generate the Signer’s signing key pair. SAM uses the CM
to generate and securely store the signing key pair for the Signer. The signing key is generated
in the HSM then its encrypted with a key held in the HSM. The encrypted key is then backed
up securely to the database.
Once the signing key pair has been generated, the SAM transforms the R.SVD (the public key)
to a CSR and gets it signed with the remote signing private key, i.e. self-signed. In response to
signing key pair generation request, the RAS Service returns the CSR which the Business
Application can send to an issuing CA to get a signing certificate. Once the Business Application
has obtained the signing certificate from the issuing CA, the Signer registration process is
considered complete.
The TOE guarantees that the Signer is the owner of the R.Signer object.
#FDP_ACC.1/Signer Maintenance
#FDP_ACF.1/Signer Maintenance
The Business Application and the Operator can modify the R.Signer’s security attributes
according to the R.Reference_Signer_Authentication_Data.
#FDP_ACC.1/Signer Key Pair Deletion
#FDP_ACF.1/Signer Key Pair Deletion
If the Business Application or the Operator requests the deletion of R.Signing_Key_Id then the
TOE deletes the R.Signing Key Id and R.SVD from R.Signer in Ascertia ADSS Server SAM
database. It also deletes the encrypted signing key from database.
#FDP_ACC.1/Supply DTBS/R
#FDP_ACF.1/Supply DTBS/R
To sign a PDF document, e.g. create a PAdES Part-4 LTV signature, the Business Application
computes the PDF document hash and then puts it into the signed attributes of CAdES
signature structure. The Business Application may also define the signature appearance
attributes and meta information before the PDF document signed. Once the CAdES signature
structure is ready then Business Application computes the hash (R.DTBS/R) over the CAdES
signed attributes and requests the RAS Service to sign this hash with the Signer’s signing key.
The TOE queues this authorisation request in the Ascertia ADSS Server SAM database against
the Signer details. When Signer later logs in to Go>Sign Mobile app, the authorisation request
is downloaded and shown to the Signer before Signer signs the authorisation response to
authorise the signing of R.DTBS/R with the signing key.
At this stage, as the Signer is required to sign the authorisation response XML via Go>Sign
Mobile app the RAS Service marks the signing transaction status as pending and responds to
the Business Application accordingly.
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After receiving the response that Signer’s signing transaction is pending, the Business
Application shows a message to the Signer that it should launch Go>Sign Mobile app on the
mobile device and authorise the signing transaction.
#FDP_ACC.1/Signing
#FDP_ACF.1/Signing
The Signer has sole control over its remote signing keys by a dynamic authorization
mechanism.
If not already installed, Signer would be required to first download and install the Go>Sign
Mobile app from a store depending on the mobile platform in use.
As soon as the Signer launches the Go>Sign Mobile app on the mobile device, the Signer is
asked to login (assuming not already signed in) by providing their User ID and two OTPs sent
to the users registered email address and phone number. Signer is presented the Go>Sign
Mobile app dashboard screen after successful authentication.
On first successful login, the Go>Sign Mobile app generates an authorisation key pair in the
mobile device’s secure element/enclave. To access the mobile device’s secure
element/enclave, the Go>Sign Mobile app authenticates the Signer via fingerprint/faceID
biometric authentication or device PIN.
The authentication using OTP values and authorisation key pair generation only happens when
the Signer logs in to Go>Sign Mobile app on a mobile device. On subsequent launches of the
Go>Sign app if the previous session was continued (i.e. user did not logout), the OTP
authentication step is automatically skipped.
After the authorisation key pair has been generated in the mobile device’s secure
element/enclave, the Go>Sign Mobile app generates a CSR having the User ID as the Subject
DN and the authorisation public key is set in the CSR. This CSR along with the unique Device
ID is sent to RAS Service for registration. The RAS Service communicates with the CA (TSP) to
get certificate for this CSR. The certificate is received back from the CA and then the RAS
Service provides this certificate to the ADSS Server SAM (TOE). The TOE associates the signer’s
authorisation certificate and Device ID the registered Signer’s details.
If the same Signer tries to login to Go>Sign Mobile app using another mobile device, they
would be authenticated again using OTP values and a new authorisation key pair would be
generated followed by new mobile device registration with the TOE. This would allow the
Signer to authorise the signing transactions using any of their registered mobile devices.
Once the Signer’s authorisation key pair has been generated and the mobile device has been
registered with the SAM, the Go>Sign Mobile app requests the RAS Service to provide the
pending authorisation requests. If there is an authorisation request waiting to be signed by
Signer, it is downloaded and signing transaction details are shown to the Signer.
Once Signer has seen the details of the signing transaction, he authorises it by signing the
authorisation response. As signing the authorisation response requires accessing the
authorisation private key held in the mobile device’s secure element/enclave, so it requires
Signer to authenticate via their fingerprint. After successful fingerprint authentication,
Go>Sign Mobile app signs the authorisation response with the authorisation private key.
Security Target Ascertia ADSS Server SAM
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The authorisation request is composed of an XML structure. Go>Sign Mobile app puts the
Device ID into the XML and then signs this – this data structure is referred to as the
authorisation response message. This authorisation response message is sent to RAS Service
for verification. The RAS Service in turn gets the SAM to verify the authorisation response
message using the authorisation public key certificate already available in the Signer’s details.
The SAM also verifies all the other details inside the authorisation response message e.g. the
mobile device ID, salt information, validity dates etc. The SAM records the authorisation
response message in its database log records, and then communicates with the CM over a
trusted channel to activate the user’s signing key. The returned signature value from the CM
is returned back to the RAS Service by the SAM.
SAM authorises itself against the CM before it activates a remote signing key in the CM. The
key authorisation is achieved by invoking the "AuthoriseKey" function of the CM. The
"AuthoriseKey" function uses the public key part of the user’s authorisation key pair. The CM
generates a challenge which is signed by the SAM using user’s authorisation private key. If the
signer is authorised and SAM is authorised to CM, it imports the Signer’s encrypted signing
key from the database, decrypts it, create the signature then deletes the decrypted signing
key.
The TOE ensures that Signer shall authorise any subsequent use of the signing key.
#FDP_ACC.1/TOE Maintenance
#FDP_ACF.1/TOE Maintenance
#FMT_MTD.1
#FMT_SMF.1
#FDP_IFC.1/Privileged user
#FDP_IFF.1/Privileged user
Only an authorised Ascertia ADSS Server SAM Operator can maintain the TOE configuration
data via Ascertia ADSS Server SAM Admin Console. There is an Access Control module in
Ascertia ADSS Server SAM Admin Console which allows creating the Ascertia ADSS Server SAM
Operator Roles. At the time of creating a new operator, one of the available role is assigned
to the operator. Each role defines what an operator is allowed to do, e.g. can it create other
Operators, register Business Applications, create infrastructure keys/certificates, create RAS
Profiles, etc.. Roles can even restrict read/write/delete access on the allowed modules.
#FDP_ETC.2/Signer
#FDP_ITC.2/Signer
#FDP_ETC.2/Privileged user
#FDP_ITC.2/Privileged user
The TOE does not import or export Signer data. Privileged User data can be exported and
imported.
7.1.4 Data protection (TSF_DP)
#FPT_PHP.1 Passive detection of physical attack
The TOE implements security functionality against physical tamper.
Security Target Ascertia ADSS Server SAM
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#FPT_PHP.3 Resistance to physical attack
The TOE detects when the enclosure of the TOE is opened and zeroises sensitive data, and
terminates main power. This ensures that the integrity and confidentiality of the assets are
preserved. During tamper state, all functionality of the TOE is stopped and no service is
provided (both signatory ones and administrative ones) even if the TOE is hardware restarted.
When the TOE is hardware restarted it will maintain the tamper state such that the previous
tamper condition can be reported.
#FPT_RPL.1 Replay detection
The TOE rejects the signature operation if a SAD is being used more than once. The
communication between RAS Service and Signer are based on a proprietary SAP. The SAP is
protected against replay, bypass and forgery attack, using a salt (random value to avoid replay
attack), a validity period and the PKCS#1 authorization signature of the Signer.
#FPT_STM.1 Reliable time stamps
The source of date and time is the system clock where TOE is deployed. To make sure TOE
uses reliable time, one or more NTP Servers can be configured to ensure its clock is synched
with a trusted clock. In case of time deviation is detected by the TOE, it suspends its
operations, i.e. R.Signer creation, signature creation, etc.
#FPT_TDC.1 Inter-TSF basic TSF data consistency
Whenever the TOE exchanges sensitive data with other components outside of the TOE
boundary uses data integrity either on the data or on the communication channel when
interpreting the data. The TOE guarantees that the interpretation of main resources will
remain consistent. However, some of the main resources of the TOE are stored outside of the
TOE. These resources are handled appropriately concerning integrity and confidentiality.
TOE ensures integrity of resources stored in Ascertia ADSS Server SAM database. The integrity
of the records stored in Ascertia ADSS Server SAM database is protected by sequenced HMAC.
The HMAC secret key is stored in the CM. Confidential data is stored in the CM or stored in
Ascertia ADSS Server SAM database encrypted by AES 256-bit symmetric keys stored in the
CM.
7.1.5 Audit (TSF_AUDIT)
#FAU_GEN.1 Audit Generation
#FAU_GEN.2 User identity association
The TOE uses an audit Database outside the TOE boundaries. The TOE logs every security
related events into the Database. Each audit record contains date and time of the event (using
reliable timestamp), type of event, subject identity (the identity of the user that caused the
event if applicable, i.e. an identified user initiated the event), and the outcome (success or
failure) of the event. The audit trail does not include any data which allows the retrieval of
sensitive data.
The integrity of the data stored in any of the tables of the Database is protected by sequenced
HMAC approach. The HMAC symmetric key is securely held in the CM.
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7.1.6 Communication protection (TSF_COMM)
#FDP_UCT.1 Basic data exchange confidentiality
#FDP_UIT.1 Data exchange integrity
#FTP_TRP.1/SSA FTP_TRP.1/SIC Trusted path
#FTP_ITC.1/CM Inter-TSF trusted channel
The TOE provides protection of user data while in transit. It ensures both confidentiality and
integrity. The SIC securely communicates with the RAS Service module, the SCA with the SSA
and the SSA with the TOE over TLS v1.2 channel. Communication with the CM is through a
secure channel using vendor specific APIs commands. Ascertia ADSS Server SAM Operators (as
Privileged Users) access the Ascertia ADSS Server SAM Admin Console GUI over a mutually
authenticated TLS v1.2 channel.
7.2 Fulfilment of the SFRs
This section shows that the TSFs are appropriate to fulfil the TOE Security Functional
Requirements as specified in chapter 6.3.
The mapping of SFRs and TSFs is given in table 7.1. Table SFR - TSF relationship.
SFR TSF
FAU_GEN.1 TSF_AUDIT
FAU_GEN.2 TSF_AUDIT
FCS_CKM.1/* TSF_CRYPTO
FCS_CKM.4 TSF_CRYPTO
FCS_COP.1/* TSF_CRYPTO
FCS_RNG.1 TSF_CRYPTO
FDP_ACC.1/Privileged User Creation TSF_CTRL
FDP_ACF.1/Privileged User Creation TSF_CTRL
FDP_ACC.1/Signer Creation TSF_CTRL
FDP_ACF.1/Signer Creation TSF_CTRL
FDP_ACC.1/Signer Key Pair Generation TSF_CTRL, TSF_DP
FDP_ACF.1/Signer Key Pair Generation TSF_CTRL
FDP_ACC.1/Signer Maintenance TSF_CTRL
FDP_ACF.1/Signer Maintenance TSF_CTRL
FDP_ACC.1/Signer Key Pair Deletion TSF_CTRL
FDP_ACF.1/Signer Key Pair Deletion TSF_CTRL
FDP_ACC.1/Supply DTBS/R TSF_CTRL
FDP_ACF.1/Supply DTBS/R TSF_CTRL
FDP_ACC.1/Signing TSF_CTRL
FDP_ACF.1/Signing TSF_CTRL
FDP_ACC.1/TOE Maintenance TSF_CTRL
FDP_ACF.1/TOE Maintenance TSF_CTRL
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SFR TSF
FDP_ETC.2/Signer 213
FDP_IFC.1/Signer TSF_CTRL
FDP_IFF.1/Signer TSF_CTRL
FDP_ETC.2/Privileged User TSF_CTRL
FDP_IFC.1/Privileged user TSF_CTRL
FDP_IFF.1/Privileged User TSF_CTRL
FDP_ITC.2/Signer 214
FDP_ITC.2/Privileged User TSF_CTRL
FDP_UCT.1 TSF_COMM
FDP_UIT.1 TSF_COMM
FIA_AFL.1/* TSF_AUTH
FIA_ATD.1 TSF_AUTH
FIA_UAU.1 TSF_AUTH
FIA_UAU.5/Signer TSF_AUTH
FIA_UAU.5/Privileged User TSF_AUTH
FIA_UID.2 TSF_AUTH
FIA_USB.1 TSF_AUTH
FMT_MSA.1/Signer TSF_CTRL
FMT_MSA.1/Privileged User TSF_CTRL
FMT_MSA.2 TSF_AUTH, TSF_CTRL
FMT_MSA.3/Signer TSF_CTRL
FMT_MSA.3/Privileged User TSF_CTRL
FMT_MTD.1 TSF_CTRL
FMT_SMF.1 TSF_CTRL
FMT_SMR.2 TSF_AUTH
FPT_PHP.1 TSF_DP
FPT_PHP.3 TSF_DP
FPT_RPL.1 TSF_DP
FPT_STM.1 TSF_AUDIT
FPT_TDC.1 TSF_DP
FPT_TRP.1/SSA TSF_COMM
FPT_TRP.1/SIC TSF_COMM
FPT_ITC.1/CM TSF_COMM
Table 7-1: SFR – TSF relationship
7.2.1 Security Requirements Coverage
Each TOE Security Functional Requirement is implemented by at least one Security Function
(see 7.1. Table SFR - TSF relationship)
213
Since the TOE does not export user data then FDP_ETC.2/Signer is trivially satisfied.
214 Since the TOE does not export user data then FDP_ITC.2/Signer is trivially satisfied
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8. Glossary and Acronyms
8.1 Acronyms
AC Access Control
API Application Programming Interface
CA Certification Authority
CC Common Criteria, ISO/IEC 15408, Evaluation criteria for IT security
CM Cryptography Module certified according to prEN 419 221-5:2016
CSR Certificate Signing Request
Certificate Certificate for electronic signature as defined in eIDAS article 3.
DTBS/R Data To Be Signed Representation
EAL Evaluation Assurance Level
HMAC Hash-based Message Authentication Code
HSM Hardware Security Module
KEK Key Encryption Key
OTP One-Time Password
RDBMS Relational database management system
SAD Signature Activation Data
SAM Signature Activation Module
SAP Signature Activation Protocol
SCA Signature Creation Application
SIC Signer’s Interaction Component
SSA Server Signing Application
SVD Signature Verification Data
ST Security Target
TOE Target of Evaluation
TSP Trust Service Provider
TW4S Trustworthy System Supporting Server Signing
QSCD Qualified Electronic Signature (or Electronic Seal) Creation Device as defined
in the eIDAS Regulation [8]
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9. Bibliography
[1] Common Criteria for Information Technology Security Evaluation, Part 1: Introduction
and General Model; CCMB-2017-04-001, Version 3.1, Revision 5, April 2017
[2] Common Criteria for Information Technology Security Evaluation, Part 2: Security
Functional Components; CCMB-2017-04-002, Version 3.1, Revision 5, April 2017
[3] Common Criteria for Information Technology Security Evaluation, Part 3: Security
Assurance Requirements; CCMB-2017-04-003, Version 3.1, Revision 5, April 2017
[4] Common Methodology for Information Technology Security Evaluation, Evaluation
Methodology; CCMB-2017-04-004, Version 3.1, Revision 5, April 2017
[5] prEN 419241-2: 2017, Trustworthy Systems Supporting Server Signing - Part 2:
Protection Profile for QSCD for Server Signing, May 2018, v.016
[6] prEN 419241-1:2017, Trustworthy Systems Supporting Server Signing Part 1: General
System Security Requirements
[7] prEN 419221-5:2016, Protection profiles for Trust Service Provider Cryptographic
modules - Part 5: Cryptographic Module for Trust Services
[8] REGULATION (EU) No 910/2014 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL
of 23 July 2014 on electronic identification and trust services for electronic transactions
in the internal market and repealing Directive 1999/93/EC
[9] ETSI TS 119 312 v1.2.1 (2017-05) Electronic Signature and Infrastructures (ESU);
Cryptographic Suites
[10] SOG-IS, Crypto Evaluation Scheme, Agreed Cryptographic Mechanisms, version 1.0,
2016
[11] ETSI EN 319 411-1 v1.1.1 (2016-02) Electronic Signatures and Infrastuctures (ESI); Policy
and security requirements for Trust Service Providers issuing certificates; Part 1: General
requirements
[12] ETSI EN 319 411-2 v2.1.1 (2016-02) Electronic Signatures and Infrastuctures (ESI); Policy
and security requirements for Trust Service Providers issuing certificates; Part 2:
Requirements for trust service providers issuing EU qualified certificates
[13] COMMISSION IMPLEMENTING DECISION (EU) 2015/1506 of 8 September 2015 laying
down specifications relating to formats of advanced electronic signatures and advanced
seals to be recognised by public sector bodies pursuant to Articles 27(5) and 37(5) of
Regulation (EU) No 910/2014 of the European Parliament and of the Council on
electronic identification and trust services for electronic transactions in the internal
market.
[14] COMMISSION IMPLEMENTING REGULATION (EU) 2015/1502 of 8 September 2015 on
setting out minimum technical specifications and procedures for assurance levels for
electronic identification means pursuant to Article 8(3) of Regulation (EU) No 910/2014
of the European Parliament and of the Council on electronic identification and trust
services for electronic transactions in the internal market.
[15] RSA Laboratories, PKCS #1: RSA Encryption Standard, Version v2.2, October 27, 2012
Security Target Ascertia ADSS Server SAM
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[16] FIPS PUB 186-4, Federal Information Processing Standards Publication, Digital Signature
Standard (DSS), July 2013
[17] FIPS PUB 140-2, Federal Information Processing Standards Publication, Security
Requirements for Cryptographic Modules, May 25, 2001
[18] X9.62-1998, Public Key Cryptography For The Financial Services Industry: The Elliptic
Curve Digital Signature Algorithm (ECDSA), September 20, 1998
[19] RFC 2104 – HMAC: Keyed-Hashing for Message Authentication, February 1997
[20] BSI AIS 20 / AIS 31, Functionality classes for random number generators Version 2.0, 18
September 2011
[21] NIST Special Publication 800-90A Recommendation for Random Number Generation
Using Deterministic Random Bit Generators, June 2015
[22] ISO/IEC 19790:2012 Information technology – Security techniques – security
requirements for cryptographic modules
[23] AGD_OPE: Operational User Guidance
[24] AGD_PRE: Preparation Procedure