Security Target Junos OS 20.3R1 for ACX5448-M Juniper Networks
Version 1.5 Page 1 of 43
Security Target Junos OS 20.3R1 for ACX5448-M
Juniper Networks
Version 1.5
March 10, 2021
Prepared for:
Juniper Networks, Inc.
1133 Innovation Way
Sunnyvale, CA 94089
www.juniper.net
Security Target Junos OS 20.3R1 for ACX5448-M Juniper Networks
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Abstract
This document provides the basis for an evaluation of a specific Target of Evaluation (TOE), Junos OS
20.3R1 for ACX5448-M. This Security Target (ST) is conformant to the requirements of Collaborative
Protection Profile for Network Devices v2.1 [NDcPP2.1].
This ST does not claim conformance to and neither is this version of the TOE conformant to the NIAP
Extended Package for MACsec Ethernet Encryption Version 1.2 (pp_ndcpp_macsec_ep_v1.2).
References
[CC1] Common Criteria for Information Technology Security Evaluation, Part 1: Introduction
and General Model, CCMB-2017-04-001, Version 3.1 Revision 5, April 2017
[CC2] Common Criteria for Information Technology Security Evaluation, Part 2: Security
Functional Components, CCMB-2017-04-002, Version 3.1 Revision 5, April 2017.
[CC3] Common Criteria for Information Technology Security Evaluation, Part 3: Security
Assurance Components, CCMB-2017-04-003, Version 3.1 Revision 5, April 2017
[CEM] Common Methodology for Information Technology Security Evaluation, Evaluation
Methodology, CCMB-2017-04-004, Version 3.1, Revision 5, April 2017.
[CC_Add] CC and CEM Addenda, Exact Conformance, Selection-Based SFRs, Optional SFRs, CCDB-
2017-05-xxx, Version 0.5, May 2017.
[NDcPP2.1] Collaborative Protection Profile for Network Devices (NDcPP), Version 2.1, 24-
September-2018
[SD] Supporting Document, Evaluation Activities for Network Device cPP, September-2018,
version 2.1
Product Guide References
[CCG] Junos OS Common Criteria Configuration Guide for ACX5448-M Devices, 12-November-
2020
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Table of Contents
1 Introduction ....................................................................................................................................5
1.1 ST reference ............................................................................................................................5
1.2 TOE Reference.........................................................................................................................5
1.3 About this document ..............................................................................................................5
1.4 Document Conventions ..........................................................................................................5
1.5 TOE Overview..........................................................................................................................6
1.6 TOE Description.......................................................................................................................6
1.6.1 Overview .........................................................................................................................6
1.6.2 Physical boundary ...........................................................................................................7
1.6.3 Logical Scope of the TOE.................................................................................................8
1.6.4 Non-TOE hardware/software/firmware .........................................................................9
1.6.5 Summary of out scope items ..........................................................................................9
2 Conformance Claims.....................................................................................................................10
2.1 CC Conformance Claim..........................................................................................................10
2.2 PP Conformance claim ..........................................................................................................10
2.3 Conformance Rationale ........................................................................................................10
2.4 Technical Decisions ...............................................................................................................10
3 Security Problem Definition..........................................................................................................13
3.1 Threats ..................................................................................................................................13
3.2 Assumptions..........................................................................................................................14
3.3 Organizational Security Policies............................................................................................15
4 Security Objectives........................................................................................................................16
4.1 Security Objectives for the TOE ............................................................................................16
4.2 Security Objectives for the Operational Environment..........................................................16
4.3 Security Objectives rationale ................................................................................................16
5 Security Functional Requirements................................................................................................17
5.1 Security Audit (FAU)..............................................................................................................17
5.1.1 Security Audit Data generation (FAU_GEN)..................................................................17
5.1.2 Security audit event storage (Extended – FAU_STG_EXT)............................................19
5.2 Cryptographic Support (FCS).................................................................................................20
5.2.1 Cryptographic Key Management (FCS_CKM)................................................................20
5.2.2 Cryptographic Operation (FCS_COP) ............................................................................21
5.2.3 FCS_RBG_EXT.1 Random Bit Generation......................................................................21
5.2.4 Cryptographic Protocols (Extended – FCS_SSHS_EXT SSH) ..........................................22
5.3 Identification and Authentication (FIA) ................................................................................22
5.3.1 Authentication Failure Management (FIA_AFL) ...........................................................22
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5.3.2 Password Management (Extended – FIA_PMG_EXT)...................................................23
5.3.3 User Identification and Authentication (Extended – FIA_UIA_EXT) .............................23
5.3.4 User authentication (FIA_UAU) (Extended – FIA_UAU_EXT)........................................23
5.4 Security Management (FMT) ................................................................................................23
5.4.1 Management of functions in TSF (FMT_MOF)..............................................................23
5.4.2 Management of TSF Data (FMT_MTD) .........................................................................24
5.4.3 Specification of Management Functions (FMT_SMF)...................................................24
5.4.4 Security management roles (FMT_SMR) ......................................................................24
5.5 Protection of the TSF (FPT) ...................................................................................................25
5.5.1 Protection of TSF Data (Extended – FPT_SKP_EXT) ......................................................25
5.5.2 Protection of Administrator Passwords (Extended – FPT_APW_EXT)..........................25
5.5.3 TSF testing (Extended – FPT_TST_EXT) .........................................................................25
5.5.4 Trusted Update (FPT_TUD_EXT) ...................................................................................25
5.5.5 Time stamps (Extended – FPT_STM_EXT)) ...................................................................26
5.6 TOE Access (FTA)...................................................................................................................26
5.6.1 TSF-initiated Session Locking (Extended – FTA_SSL_EXT) ............................................26
5.6.2 Session locking and termination (FTA_SSL) ..................................................................26
5.6.3 TOE access banners (FTA_TAB).....................................................................................26
5.7 Trusted path/channels (FTP).................................................................................................27
5.7.1 Trusted Channel (FTP_ITC)............................................................................................27
5.7.2 Trusted Path (FTP_TRP).................................................................................................27
6 Security Assurance Requirements ................................................................................................28
7 TOE Summary Specification..........................................................................................................29
7.1 Security Audit........................................................................................................................29
7.2 Cryptographic Support..........................................................................................................31
7.2.1 Algorithms and zeroization...........................................................................................31
7.2.2 Random Bit Generation ................................................................................................34
7.2.3 SSH ................................................................................................................................34
7.3 Identification and Authentication.........................................................................................37
7.4 Security Management...........................................................................................................39
7.5 Protection of the TSF ............................................................................................................40
7.6 TOE Access ............................................................................................................................41
7.7 Trusted path/Trusted Channels ............................................................................................41
8 Glossary.........................................................................................................................................42
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1 Introduction
1. This section identifies the Security Target (ST), Target of Evaluation (TOE), Security Target
organization, document conventions, and terminology. It also includes an overview of the
evaluated products.
1.1 ST reference
ST Title Security Target Junos OS 20.3R1 for ACX5448-M
ST Revision 1.5
ST Date March 10, 2021
Author Juniper Networks, Inc.
cPP/EP Conformance [NDcPP2.1]
1.2 TOE Reference
TOE Title Junos OS 20.3R1 for ACX5448-M
TOE Firmware Junos OS 20.3R1
1.3 About this document
2. This Security Target follows the following format:
Section Title Description
1 Introduction Provides an overview of the TOE and defines the hardware and
firmware that make up the TOE as well as the physical and logical
boundaries of the TOE
2 Conformance Claims Lists evaluation conformance to Common Criteria versions,
Protection Profiles, or Packages where applicable
3 Security Problem Definition Specifies the threats, assumptions and organizational security
policies that affect the TOE
4 Security Objectives Defines the security objectives for the TOE/operational
environment and provides a rationale to demonstrate that the
security objectives satisfy the threats
5 Security Functional
Requirements
Contains the functional requirements for this TOE
6 Security Assurance
Requirements
Contains the assurance requirements for this TOE
7 TOE Summary Specification Identifies the IT security functions provided by the TOE and also
identifies the assurance measures targeted to meet the
assurance requirements
8 Glossary Identifies the terminology used in the ST.
Table 1 Document Organization
1.4 Document Conventions
3. This document follows the same conventions as those applied in [NDcPP2.1] in the completion
of operations on Security Functional Requirements, namely:
• Unaltered SFRs are stated in the form used in [CC2] or their extended component definition
(ECD);
• Refinement made in the ST: the refinement text is indicated with bold text and
strikethroughs;
• Selection completed in the ST: the selection values are indicated with underlined text
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e.g. “[selection: disclosure, modification, loss of use]” in [CC2] or an ECD might
become “disclosure” (completion);
• Assignment completed in the ST: indicated with italicized text;
• Assignment completed within a selection in the ST: the completed assignment text is
indicated with italicized and underlined text
e.g. “[selection: change_default, query, modify, delete, [assignment: other
operations]]” in [CC2] or an ECD might become “change_default, select_tag”
(completion of both selection and assignment);
• Iteration: indicated by adding a string starting with “/” (e.g. “FCS_COP.1/Hash”).
1.5 TOE Overview
4. The Target of Evaluation (TOE) is Juniper Networks, Inc. Junos OS 20.3R1 executing on ACX5000
series universal metro router model ACX5448-M. The Routing Engine is in-built without separate
component identification.
5. ACX5448-M appliance is a secure network device that protects itself largely by offering only a
minimal logical interface to the network and attached nodes. It is powered by the Junos OS
firmware, Junos OS 20.3R1, which is a special purpose OS that provides no general purpose
computing capability. Junos OS provides both management and control functions as well as all IP
routing.
6. The appliance primarily supports the definition and enforcement of information flow policies
among network nodes. All information flow from one network node to another passes through
an instance of the TOE. Information flow is controlled on the basis of network node addresses
and protocol. In support of the information flow security functions, the TOE ensures that
security-relevant activity is audited and provides the tools to manage all of the security
functions.
1.6 TOE Description
1.6.1 Overview
7. The ACX5448-M Universal Metro Router is a complete routing system that supports a variety of
high-speed interfaces (only Ethernet is within scope of the evaluation) for metro networks and
network applications. It shares with other ACF5000 variants the common Junos firmware,
features, and technology for compatibility across platforms.
8. The appliance is physically self-contained, housing all firmware and hardware necessary to
perform all routing functions. The architecture components of the appliances are:
• Switch fabric – the switch fabric boards/modules provide a highly scalable, non-blocking,
centralized switch fabric matrix through which all network data passes.
• Routing Engine (Control Board) – the Routine Engine (RE) runs the Junos firmware and
provides Layer 3 routing services and Layer 2 switching services. The RE also provides
network management for all operations necessary for the configuration and operation of the
TOE and controls the flow of information through the TOE, including support for appliance
interface control and control plane functions such as chassis component, system
management and user access to the appliance.
• Layer 2 switching services, Layer 3 switching/routing services and network management for
all operations necessary for the configuration and operation of the TOE and to control the
flow of information through the TOE.
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• The Packet Forwarding Engine (PFE) – provides all operations necessary for transit packet
forwarding. This is provided by the Modular Port Concentrators on the appliances and Line
Cards. The ACX5448-M line cards support an extensive set of Layer 2 and Layer 3 services
that can be deployed in any combination of L2- L3 applications.
• Power – power supply bays to provide complete flexibility for provisioning and redundancy.
The power supplies connect to the midplane, which distributes the different output voltages
produced by the power supplies to the appliance components, depending on their voltage
requirements.
9. The RE and PFE perform their primary tasks independently, while constantly communicating
through a high-speed internal link. This arrangement provides streamlined forwarding and
routing control and the capability to run Internet-scale networks at high speeds.
10. The appliance supports numerous routing and switching standards for flexibility and scalability.
11. The functions of the appliance can all be managed through the Junos firmware, either from a
connected terminal console or via a network connection. Network management is secured using
the SSH protocol. All management, whether from a user connecting to a terminal or from the
network, requires successful authentication. In the evaluated deployment the TOE is managed
and configured via Command Line Interface, either via a directly connected console or over the
network secured using the SSH protocol.
1.6.2 Physical boundary
12. The TOE is the Junos OS 20.3R1 firmware running on the appliance chassis. Hence, the TOE is
contained within the physical boundary of the specified appliance chassis, as shown in Figure 1.
The physical boundary of the TOE is the entire chassis of the appliance ACX5448-M with an in-
built routing engine and an in-built line card.
Figure 1 ACX5448-M TOE Boundary
13. The TOE interfaces are comprised of the following:
a) Network interfaces which pass traffic
b) Management interface through which handle administrative actions.
14. The ACX5448-M appliance supports numerous combinations and permutations of line cards in
the network ports. The interface options supported are described in the following:
• https://www.juniper.net/documentation/en_US/release-
independent/junos/information-products/pathway-pages/acx-series/acx5448/acx5448-
hwguide.pdf
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15. A jinstall image is provided for the ACX5448-M:
• junos-vmhost-install-x86-64-20.3R1.8.tgz
16. The firmware version reflects the detail reported for the components of the Junos OS when the
“show version” command is executed on the appliance.
17. The guidance documents included as part of the TOE are:
[ECG] Junos OS Common Criteria Configuration Guide for ACX5448-M Devices, 12-November-
2020
1.6.3 Logical Scope of the TOE
18. The logical boundary of the TOE includes the following security functionality:
Security Functionality Description
Security Audit Auditable events are stored in the syslog files on the
appliance and can be sent to an external log server (via
Netconf over SSH). Auditable events include start-up and
shutdown of the audit functions, authentication events,
and all events listed in Table 8. Audit records include the
date and time, event category, event type, username, and
the outcome of the event (success or failure). Local syslog
storage limits are configurable and are monitored. If the
storage limit is reached the oldest logs will be overwritten.
Cryptographic Support The TOE provides an SSH server to support protected
communications for administrators to establish secure
sessions and to connect to external syslog servers.
The TOE requires that applications exchanging information
with it are successfully authenticated prior to any exchange
(i.e. applications connecting over SSH).
The TOE includes cryptographic modules that provide the
underlying cryptographic services, including key
management and protection of stored keys, algorithms,
random bit generation and crypto-administration. The
cryptographic modules provide confidentiality and integrity
services for authentication and for protecting
communications with connecting applications.
Identification and
Authentication
The TOE supports Role Based Access Control. All users
must be authenticated to the TOE prior to being granted
access to any management actions. The TOE supports
password based authentication and public key based
authentication. Based on the assigned role, a user is
granted a set of privileges to access the system.
Administrative users must provide unique identification
and authentication data before any administrative access
to the system is granted. Authentication data entered and
stored on the TOE is protected.
Security Management The TOE provides a Security Administrator role that is
responsible for:
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• the configuration and maintenance of cryptographic
elements related to the establishment of secure
connections to and from the evaluated product
• the regular review of all audit data;
• initiation of trusted update function;
• all administrative tasks (e.g., creating the security policy).
The devices are managed through a Command Line
Interface (CLI). The CLI is accessible through local (serial)
console connection or remote administrative (SSH) session.
Protection of the TSF The TOE protects all passwords, pre-shared keys,
symmetric keys and private keys from unauthorized
disclosure. Passwords are stored in encrypted format.
Passwords are stored using sha256 or sha512. The TOE
executes self-tests during initial start-up to ensure correct
operation and enforcement of its security functions. An
administrator can install software updates to the TOE. The
TOE internally maintains the date and time.
TOE Access Prior to establishing an administration session with the
TOE, a banner is displayed to the user. The banner
messaging is customizable. The TOE will terminate an
interactive session after a period of inactivity. A user can
terminate their local CLI session and remote CLI session by
entering exit at the prompt.
Trusted Path/Trusted
Channel
The TOE supports SSH v2 for secure communication to
Syslog server. The TOE supports SSH v2 (remote CLI) for
secure remote administration.
Table 2 Logical Scope of TOE
1.6.4 Non-TOE hardware/software/firmware
19. The TOE relies on the provision of the following items in the network environment:
• Syslog server supporting SSHv2 connections to send audit logs;
• SSHv2 client for remote administration;
• Serial connection client for local administration.
1.6.5 Summary of out scope items
• Use of telnet, since it violates the Trusted Path requirement set (see Section 5.7.2)
• Use of FTP, since it violates the Trusted Path requirement set (see Section 5.7.2)
• Use of SNMP, since it violates the Trusted Path requirement set (see Section 5.7.2)
• Use of SSL, including management via J-Web, JUNOScript and JUNOScope, since it violates
the Trusted Path requirement set (see Section 5.7.2)
• Use of CLI account super-user and linux root account.
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2 Conformance Claims
2.1 CC Conformance Claim
20. The TOE and ST are compliant with the Common Criteria (CC) Version 3.1, Revision 5, dated:
April 2017.
21. This TOE is conformant to:
• Common Criteria for Information Technology Security Evaluations Part 1, Version 3.1,
Revision 5, April 2017
• Common Criteria for Information Technology Security Evaluations Part 2, Version 3.1,
Revision 5, April 2017: Part 2 extended
• Common Criteria for Information Technology Security Evaluations Part 3, Version 3.1,
Revision 5, April 2017: Part 3 conformant
2.2 PP Conformance claim
22. This TOE claims exact conformance to [NDcPP2.1] identified below. Exact conformace is defined
in Sect. 2 of [NDcPP2.1] and in [CC_Add].
• [NDcPP2.1] Collaborative Protection Profile for Network Devices (NDcPP), Version 2.1, 24-
September-2018
23. This ST does not claim conformance to and neither is this version of the TOE conformant to the
NIAP Extended Package for MACsec Ethernet Encryption Version 1.2
(pp_ndcpp_macsec_ep_v1.2).
2.3 Conformance Rationale
24. This Security Target provides exact conformance to Version 2.1 of the Collaborative Protection
Profile for Network Devices. The security problem definition, security objectives and security
requirements in this Security Target are all taken from the Protection Profile performing only
operations defined there.
2.4 Technical Decisions
25. This section identifies all NIAP Technical Decisions that are applicable to this TOE:
Technical Decisions applicable to NDcPP v2.1
Technical Decisions Applicable Exclusion Rationale (if
applicable)
TD0547: NIT Technical Decision for Clarification on
developer disclosure of AVA_VAN
Yes
TD0538: NIT Technical Decision for Outdated link to
allowed-with list
Yes
TD0536: NIT Technical Decision for Update
Verification Inconsistency
Yes
TD0535: NIT Technical Decision for Clarification
about digital signature algorithms for FTP_TUD.1
Yes
TD0533: NIT Technical Decision for FTP_ITC.1 with
signed downloads
Yes
TD0532: NIT Technical Decision for Use of seeds
with higher entropy
Yes
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TD0531: NIT Technical Decision for Challenge-
Response for Authentication
Yes
TD0530: NIT Technical Decision for
FCS_TLSC_EXT.1.1 5e test clarification
No No FCS_TLSC_EXT claimed
TD0529: NIT Technical Decision for OCSP and
Authority Information Access extension
No No FIA_X509_EXT claimed
TD0528: NIT Technical Decision for Missing EAs for
FCS_NTP_EXT.1.4
No No FCS_NTP_EXT is claimed
TD0484: NIT Technical Decision for Interactive
sessions in FTA_SSL_EXT.1 & FTA_SSL.3
Yes
TD0483: NIT Technical Decision for Applicability of
FPT_APW_EXT.1
Yes
TD0482: NIT Technical Decision for Identification of
usage of cryptographic schemes
Yes
TD0481: NIT Technical Decision for
FCS_(D)TLSC_EXT.X.2 IP addresses in reference
identifiers
No No FCS_(D)TLSC_EXT claimed
TD0480: NIT Technical Decision for Granularity of
audit events
Yes
TD0478: NIT Technical Decision for Application
Notes for FIA_X509_EXT.1 iterations
No No FIA_X509_EXT claimed
TD0477: NIT Technical Decision for Clarifying
FPT_TUD_EXT.1 Trusted Update
Yes
TD0475: NIT Technical Decision for Separate traffic
consideration for SSH rekey
Yes
TD0453: NIT Technical Decision for Clarify
authentication methods SSH clients can use to
authenticate SSH se1
No No FCS_SSHC_EXT.1 claimed
TD0452: NIT Technical Decision for
FCS_(D)TLSC_EXT.X.2 IP addresses in reference
identifiers
No This TD has been archived
and is no longer applicable.
TD0451: NIT Technical Decision for ITT Comm UUID
Reference Identifier
No No FCS_TLSS_EXT claimed.
TD0450: NIT Technical Decision for RSA-based
ciphers and the Server Key Exchange message
No No FCS_TLSS_EXT or
FCS_DTLSS_EXT claimed.
TD0449: NIT Technical Decision for Identification of
usage of cryptographic schemes
No This TD has been archived
and is no longer applicable.
TD0448: NIT Technical Decision for Documenting
Diffie-Hellman 14 groups
No This TD has been archived
and is no longer applicable.
TD0447: NIT Technical Decision for Using 'diffie-
hellman-group-exchange-sha256' in
FCS_SSHC/S_EXT.1.7
Yes
TD0425: NIT Technical Decision for Cut-and-paste
Error for Guidance AA
Yes
TD0424: NIT Technical Decision for NDcPP v2.1
Clarification - FCS_SSHC/S_EXT.1.5
Yes
TD0423: NIT Technical Decision for clarification
about application of Rfi#201726rev2
No TLS protocol and X.509
certificate support is not
being claimed
1
Presumed to be "... to authenticate SSH servers" but the wording is precisely as taken from the NIAP web site
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TD0412: NIT Technical Decision for
FCS_SSHS_EXT.1.5 SFR and AA discrepancy
Yes
TD0411: NIT Technical Decision for
FCS_SSHC_EXT.1.5, Test 1 - Server and client side
seem to be confused
No FCS_SSHC_EXT.1 is not being
claimed
TD0410: NIT technical decision for Redundant
assurance activities associated with FAU_GEN.1
Yes
TD0409: NIT decision for Applicability of FIA_AFL.1
to key-based SSH authentication
Yes
TD0408: NIT Technical Decision for local vs. remote
administrator accounts
Yes
TD0407: NIT Technical Decision for handling
Certification of Cloud Deployments
No Not a cloud deployment
TD0402: NIT Technical Decision for RSA-based
FCS_CKM.2 Selection
Yes
TD0401: NIT Technical Decision for Reliance on
external servers to meet SFRs
No TOE does not depend on the
Authentication Server to
satisfy FIA requirements
TD0400: NIT Technical Decision for FCS_CKM.2 and
elliptic curve-based key establishment
Yes
TD0399: NIT Technical Decision for Manual
installation of CRL (FIA_X509_EXT.2)
No TOE does not claim
certificate authentication of
firmware updates
TD0398: NIT Technical Decision for
FCS_SSH*EXT.1.1 RFCs for AES-CTR
Yes
TD0397: NIT Technical Decision for Fixing AES-CTR
Mode Tests
Yes
TD0396: NIT Technical Decision for
FCS_TLSC_EXT.1.1, Test 2
No FCS_TLSC_EXT.1 is not being
claimed
TD0395: NIT Technical Decision for Different
Handling of TLS1.1 and TLS1.2
No TLS protocol is not being
claimed.
Table 3 Technical Decisions
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3 Security Problem Definition
26. The security problem definition taken from [NDcPP v2.1] is reproduced here.
3.1 Threats
Threat Threat Definition
T.UNAUTHORIZED_ADMINISTRATOR
_ACCESS
Threat agents may attempt to gain Administrator access to
the network device by nefarious means such as
masquerading as an Administrator to the device,
masquerading as the device to an Administrator, replaying
an administrative session (in its entirety, or selected
portions), or performing man-in-the-middle attacks, which
would provide access to the administrative session, or
sessions between network devices. Successfully gaining
Administrator access allows malicious actions that
compromise the security functionality of the device and
the network on which it resides.
T.WEAK_CRYPTOGRAPHY Threat agents may exploit weak cryptographic algorithms
or perform a cryptographic exhaust against the key space.
Poorly chosen encryption algorithms, modes, and key sizes
will allow attackers to compromise the algorithms, or brute
force exhaust the key space and give them unauthorized
access allowing them to read, manipulate and/or control
the traffic with minimal effort.
T.UNTRUSTED_COMMUNICATION
_CHANNELS
Threat agents may attempt to target network devices that
do not use standardized secure tunnelling protocols to
protect the critical network traffic. Attackers may take
advantage of poorly designed protocols or poor key
management to successfully perform man-in-the-middle
attacks, replay attacks, etc. Successful attacks will result in
loss of confidentiality and integrity of the critical network
traffic, and potentially could lead to a compromise of the
network device itself.
T.WEAK_AUTHENTICATION
_ENDPOINTS
Threat agents may take advantage of secure protocols that
use weak methods to authenticate the endpoints – e.g. a
shared password that is guessable or transported as
plaintext. The consequences are the same as a poorly
designed protocol, the attacker could masquerade as the
Administrator or another device, and the attacker could
insert themselves into the network stream and perform a
man-in-the-middle attack. The result is the critical network
traffic is exposed and there could be a loss of
confidentiality and integrity, and potentially the network
device itself could be compromised.
T.UPDATE_COMPROMISE Threat agents may attempt to provide a compromised
update of the software or firmware which undermines the
security functionality of the device. Non-validated updates
or updates validated using non-secure or weak
cryptography leave the update firmware vulnerable to
surreptitious alteration.
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Threat Threat Definition
T.UNDETECTED_ACTIVITY Threat agents may attempt to access, change, and/or
modify the security functionality of the network device
without Administrator awareness. This could result in the
attacker finding an avenue (e.g., misconfiguration, flaw in
the product) to compromise the device and the
Administrator would have no knowledge that the device
has been compromised.
T.SECURITY_FUNCTIONALITY
_COMPROMISE
Threat agents may compromise credentials and device
data enabling continued access to the network device and
its critical data. The compromise of credentials includes
replacing existing credentials with an attacker’s
credentials, modifying existing credentials, or obtaining the
Administrator or device credentials for use by the attacker.
T.PASSWORD_CRACKING Threat agents may be able to take advantage of weak
administrative passwords to gain privileged access to the
device. Having privileged access to the device provides the
attacker unfettered access to the network traffic and may
allow them to take advantage of any trust relationships
with other network devices.
T.SECURITY_FUNCTIONALITY
_FAILURE
An external, unauthorized entity could make use of failed
or compromised security functionality and might therefore
subsequently use or abuse security functions without prior
authentication to access, change or modify device data,
critical network traffic or security functionality of the
device.
Table 4 Threats
3.2 Assumptions
27. This section describes the assumptions made in identification of the threats and security
requirements for network devices. The network device is not expected to provide assurance in
any of these areas, and as a result, requirements are not included to mitigate the threats
associated.
Assumption Assumption Definition
A.PHYSICAL_PROTECTION The network device is assumed to be physically protected in its
operational environment and not subject to physical attacks
that compromise the security and/or interfere with the
device’s physical interconnections and correct operation. This
protection is assumed to be sufficient to protect the device
and the data it contains. As a result, the cPP will not include
any requirements on physical tamper protection or other
physical attack mitigations. The cPP will not expect the
product to defend against physical access to the device that
allows unauthorized entities to extract data, bypass other
controls, or otherwise manipulate the device.
A.LIMITED_FUNCTIONALITY The device is assumed to provide networking functionality as
its core function and not provide functionality/services that
could be deemed as general purpose computing. For example
the device should not provide computing platform for general
purpose applications (unrelated to networking functionality).
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Assumption Assumption Definition
A.TRUSTED_ADMINISTRATOR
The Security Administrator(s) for the network device are
assumed to be trusted and to act in the best interest of security
for the organization. This includes being appropriately trained,
following policy, and adhering to guidance documentation.
Administrators are trusted to ensure passwords/credentials
have sufficient strength and entropy and to lack malicious
intent when administering the device. The network device is
not expected to be capable of defending against a malicious
Administrator that actively works to bypass or compromise the
security of the device. For TOEs supporting X.509v3 certificate-
based authentication, the Security Administrator(s) are
expected to fully validate (e.g. offline verification) any CA
certificate (root CA certificate or intermediate CA certificate)
loaded into the TOE’s trust store (aka 'root store', ' trusted CA
Key Store', or similar) as a trust anchor prior to use (e.g. offline
verification).
A.REGULAR_UPDATES The network device firmware and software is assumed to be
updated by an Administrator on a regular basis in response to
the release of product updates due to known vulnerabilities.
A.ADMIN_CREDENTIALS_SECURE The administrator’s credentials (private key) used to access
the network device are protected by the platform on which
they reside.
A.RESIDUAL_INFORMATION The Administrator must ensure that there is no unauthorized
access possible for sensitive residual information (e.g.
cryptographic keys, keying material, PINs, passwords etc.) on
networking equipment when the equipment is discarded or
removed from its operational environment.
Table 5 Assumptions
3.3 Organizational Security Policies
28. An organizational security policy is a set of rules, practices, and procedures imposed by an
organization to address its security needs. For the purposes of this cPP a single policy is
described in the section below.
Policy Name Policy Definition
P.ACCESS_BANNER The TOE shall display an initial banner describing restrictions of use, legal
agreements, or any other appropriate information to which users consent by
accessing the TOE.
Table 6 Organizational Security Policies
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4 Security Objectives
29. The security objectives have been taken from [NDcPP v2.1] and are reproduced here for the
convenience of the reader.
4.1 Security Objectives for the TOE
There are no security objectives for the TOE defined in [NDcPP v2.1].
4.2 Security Objectives for the Operational Environment
30. The following security objectives are defined for the Operational Environment:
Environment Security
Objective
IT Environment Security Objective Definition
OE.PHYSICAL Physical security, commensurate with the value of the TOE and
the data it contains, is provided by the environment.
OE.NO_GENERAL_PURPOSE There are no general-purpose computing capabilities (e.g.,
compilers or user applications) available on the TOE, other than
those services necessary for the operation, administration and
support of the TOE.
OE.NO_THRU_TRAFFIC
_PROTECTION
The TOE does not provide any protection of traffic that traverses
it. It is assumed that protection of this traffic will be covered by
other security and assurance measures in the operational
environment.
OE.TRUSTED_ADMIN TOE Administrators are trusted to follow and apply all
administrator guidance in a trusted manner.
For TOEs supporting X.509v3 certificate-based authentication,
the Security Administrator(s) are assumed to monitor the
revocation status of all certificates in the TOE's trust store and to
remove any certificate from the TOE’s trust store in case such
certificate can no longer be trusted.
OE.UPDATES The TOE firmware and software is updated by an Administrator
on a regular basis in response to the release of product updates
due to known vulnerabilities.
OE.ADMIN_CREDENTIALS
_SECURE
The Administrator’s credentials (private key) used to access the
TOE must be protected on any other platform on which they
reside.
OE.RESIDUAL_INFORMATION The Security Administrator ensures that there is no unauthorized
access possible for sensitive residual information (e.g.
cryptographic keys, keying material, PINs, passwords etc.) on
networking equipment when the equipment is discarded or
removed from its operational environment.
Table 7 Security Objectives for Operational Environment
4.3 Security Objectives rationale
31. As these objectives for the TOE and operational environment are identical to those specified in
[NDcPP2.1], the rationales provided in Sect. 4 thereof are wholly applicable to this ST.
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5 Security Functional Requirements
32. All security functional requirements are taken from and structured accoding to [NDcPP2.1]. The
SFRs are presented in accordance with the conventions described in [NDcPP2.1] Section 6.1, and
section 1.4 of this document.
33. As this TOE is not distributed, none of the security functional requirements relating to
distributed TOEs are specified for this TOE.
5.1 Security Audit (FAU)
5.1.1 Security Audit Data generation (FAU_GEN)
5.1.1.1 FAU_GEN.1 Audit data generation
FAU_GEN.1 Audit data generation
FAU_GEN.1.1 The TSF shall be able to generate an audit record of the following auditable events:
a) Start-up and shut-down of the audit functions;
b) All auditable events for the not specified level of audit; and
c) All administrative actions comprising:
• Administrative login and logout (name of user account shall be logged if individual user
accounts are required for Administrators).
• Changes to TSF data related to configuration changes (in addition to the information
that a change occurred it shall be logged what has been changed).
• Generating/import of, changing, or deleting of cryptographic keys (in addition to the
action itself a unique key name or key reference shall be logged).
• Resetting passwords (name of related user account shall be logged).
• [no other actions];
d) Specifically defined auditable events listed in Table 8.
ST Application Note:
If the list of “administrative actions” appears to be incomplete, the assignment in the selection
should be used to list additional administrative actions which are audited.
The requirement to audit the "Generating/import of, changing, or deleting of cryptographic keys"
refers to all types of cryptographic keys which are intended to be used longer than for just one
session (i.e. it does not refer to ephemeral keys/session keys). The requirement applies to all named
changes independently from how they are invoked. A cryptographic key could e.g. be generated
automatically during initial start-up without administrator intervention or through administrator
intervention. In all related cases the changes to cryptographic keys need to be audited together with
a unique key name, key reference or unique identifier for the corresponding certificate.
FAU_GEN.1.2 The TSF shall record within each audit record at least the following information:
a) Date and time of the event, type of event, subject identity, 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, information specified in column three of Table 8.
Requirement Auditable Events Additional Audit Record
Contents
FAU_GEN.1 None None
FAU_GEN.2 None None
FAU_STG_EXT.1 None None
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FAU_STG.1 None None
FCS_CKM.1 None None
FCS_CKM.2 None None
FCS_CKM.4 None None
FCS_COP.1/DataEncryption None None
FCS_COP.1/SigGen None None
FCS_COP.1/Hash None None
FCS_COP.1/KeyedHash None None
FCS_RBG_EXT.1 None None
FIA_PMG_EXT.1 None None
FIA_UIA_EXT.1 All use of identification and
authentication mechanism.
Origin of the attempt (e.g., IP
address)
FIA_UAU_EXT.2 All use of identification and
authentication mechanism.
Origin of the attempt (e.g., IP
address)
FIA_UAU.7 None None
FIA_AFL.1 Unsuccessful login attempts
limit is met or exceeded.
Origin of the attempt (e.g., IP
address).
FMT_MOF.1/ManualUpdate Any attempt to initiate a
manual update
None
FMT_MTD.1/CoreData None None
FMT_SMF.1 All management activities of
TSF data
None
FMT_SMR.2 None None
FPT_SKP_EXT.1 None None
FPT_APW_EXT.1 None None
FPT_TST_EXT.1 None None
FPT_TUD_EXT.1 Initiation of update; result of
the update attempt (success
or failure)
None.
FPT_STM_EXT.1 Discontinuous changes to
time - either Administrator
actuated or changed via an
automated process. (Note
that no continuous changes
to time need to be logged.
See also application note on
FPT_STM_EXT.1)
For discontinuous changes to
time: The old and new values
for the time. Origin of the
attempt to change time for
success and failure (e.g., IP
address).
FTA_SSL_EXT.1 (if “terminate
the session" is selected)
The termination of a local
interactive session by the
session locking mechanism.
None.
FTA_SSL.3 The termination of a remote
session by the session locking
mechanism.
None
FTA_SSL.4 The termination of an
interactive session.
None
FTA_TAB.1 None None
FTP_ITC.1 Initiation of the trusted
channel.
Termination of the trusted
channel.
Identification of the initiator
and target of failed trusted
channels establishment
attempt.
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Failure of the trusted channel
functions.
FTP_TRP.1/Admin Initiation of the trusted path.
Termination of the trusted
path.
Failure of the trusted path
functions.
None.
FCS_SSHS_EXT.1 Failure to establish an SSH
session
Reason for failure
FMT_MOF.1/Functions None. None.
FMT_MOF.1/Services None. None
FMT_MTD.1/CryptoKeys None. None.
Table 8 FAU_GEN.1 Security Functional Requirements and Auditable Events
5.1.1.2 FAU_GEN.2 User identity association
FAU_GEN.2 User identity association
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.
5.1.2 Security audit event storage (Extended – FAU_STG_EXT)
5.1.2.1 FAU_ STG_EXT.1 Protected Audit Event Storage
FAU_STG_EXT.1 Protected Audit Event Storage
FAU_STG_EXT.1.1 The TSF shall be able to transmit the generated audit data to an external IT entity
using a trusted channel according to FTP_ITC.1.
ST Application Note
Transfer of the audit data to the external server is performed automatically (without further Security
Administrator intervention) in the evaluated deployment.
FAU_STG_EXT.1.2 The TSF shall be able to store generated audit data on the TOE itself.
[
• TOE shall consist of a single standalone component that stores audit data locally].
FAU_STG_EXT.1.3 The TSF shall [overwrite previous audit records according to the following rule:
[oldest log is overwritten]] when the local storage space for audit data is full.
5.1.2.2 FAU_STG.1 Protected audit trail storage (Optional)
FAU_STG.1 Protected audit trail storage
FAU_STG.1.1 The TSF shall protect the stored audit records in the audit trail from unauthorised
deletion.
FAU_STG.1.2 The TSF shall be able to prevent unauthorised modifications to the stored audit
records in the audit trail.
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5.2 Cryptographic Support (FCS)
5.2.1 Cryptographic Key Management (FCS_CKM)
5.2.1.1 FCS_CKM.1 Cryptographic Key Generation (Refinement)
FCS_CKM.1 Cryptographic Key Generation
FCS_CKM.1.1 The TSF shall generate asymmetric cryptographic keys in accordance with a specified
cryptographic key generation algorithm: [
• RSA schemes using cryptographic key sizes of 2048-bit or greater that meet the
following: FIPS PUB 186-4, “Digital Signature Standard (DSS)”, Appendix B.3;
• ECC schemes using “NIST curves” [P-256, P-384, P-521] that meet the following: FIPS PUB
186-4, “Digital Signature Standard (DSS)”, Appendix B.4;
• FFC Schemes using Diffie-Hellman group 14 that meet the following: RFC 3526, Section 3
] and specified cryptographic key sizes [assignment: cryptographic key sizes] that meet the
following: [assignment: list of standards].
5.2.1.2 FCS_CKM.2 Cryptographic Key Establishment (Refinement)
FCS_CKM.2 Cryptographic Key Establishment
FCS_CKM.2.12
The TSF shall perform cryptographic key establishment in accordance with a specified
cryptographic key establishment method: [
• RSA-based key establishment schemes that meet the following: RSAES-PKCS1-v1_5 as
specified in Section 7.2 of RFC 3447, “Public-Key Cryptography Standards (PKCS) #1: RSA
Cryptography Specifications Version 2.1
• Elliptic curve-based key establishment schemes that meet the following: NIST Special
Publication 800-56A Revision 2, “Recommendation for Pair-Wise Key Establishment
Schemes Using Discrete Logarithm Cryptography”;
• Key establishment scheme using Diffie-Hellman group 14 that meets the following: RFC
3526, Section 3;
] that meets the following: [assignment: list of standards].
5.2.1.3 FCS_CKM.4 Cryptographic Key Destruction
FCS_CKM.4 Cryptographic Key Destruction
FCS_CKM.4.1 The TSF shall destroy cryptographic keys in accordance with a specified cryptographic
key destruction method
• For plaintext keys in volatile storage, the destruction shall be executed by a [destruction
of reference to the key directly followed by a request for garbage collection];
• For plaintext keys in non-volatile storage, the destruction shall be executed by the
invocation of an interface provided by a part of the TSF that [
o logically addresses the storage location of the key and performs a [single
overwrite consisting of [zeroes]]
that meets the following: No Standard.
2
Revised as per TD0402
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5.2.2 Cryptographic Operation (FCS_COP)
5.2.2.1 FCS_COP.1 Cryptographic Operation
FCS_COP.1/DataEncryption Cryptographic Operation (AES Data Encryption/Decryption)
FCS_COP.1.1/DataEncryption The TSF shall perform encryption/decryption in accordance with a
specified cryptographic algorithm AES used in [CBC, CTR] mode and cryptographic key sizes [128 bits,
256 bits] that meet the following: AES as specified in ISO 18033-3, [CBC as specified in ISO 10116, CTR
as specified in ISO 10116].
FCS_COP.1/SigGen Cryptographic Operation (Signature Generation and Verification)
FCS_COP.1.1/SigGen The TSF shall perform cryptographic signature services (generation and
verification) in accordance with a specified cryptographic algorithm [
• RSA Digital Signature Algorithm and cryptographic key sizes (modulus) [2048 bits or
greater],
• Elliptic Curve Digital Signature Algorithm and cryptographic key sizes [P-256, P-384, P-
521 bits]
] and cryptographic key sizes [assignment: cryptographic key sizes]
that meet the following: [
• For RSA schemes: FIPS PUB 186-4, “Digital Signature Standard (DSS)”, Section 5.5, using
PKCS #1 v2.1 Signature Schemes RSASSA-PSS and/or RSASSA-PKCS1v1_5; ISO/IEC 9796-2,
Digital signature scheme 2 or Digital Signature scheme 3,
• For ECDSA schemes: FIPS PUB 186-4, “Digital Signature Standard (DSS)”, Section 6 and
Appendix D, Implementing “NIST curves” [P-256, P-384, P-521]; ISO/IEC 14888-3, Section
6.4
].
FCS_COP.1/Hash Cryptographic Operation (Hash Algorithm)
FCS_COP.1.1/Hash The TSF shall perform cryptographic hashing services in accordance with a
specified cryptographic algorithm [SHA-1, SHA-256, SHA-384, SHA-512] and cryptographic key sizes
[assignment: cryptographic key sizes] and message digest sizes [160, 256, 384, 512] bits that meet
the following: [ISO/IEC 10118-3:2004].
FCS_COP.1/KeyedHash Cryptographic Operation (Keyed Hash Algorithm)
FCS_COP.1.1/KeyedHash The TSF shall perform keyed-hash message authentication in accordance
with a specified cryptographic algorithm [HMAC-SHA-1, HMAC-SHA-256, HMAC-SHA-512] and
cryptographic key sizes [160, 256, 384 and 512 bits] and message digest sizes [160, 256, 512] bits
that meet the following: ISO/IEC 9797-2:2011, Section 7 “MAC Algorithm 2”.
5.2.3 FCS_RBG_EXT.1 Random Bit Generation
FCS_RBG_EXT.1 Random Bit Generation
FCS_RBG_EXT.1.1 The TSF shall perform all deterministic random bit generation services in
accordance with ISO/IEC 18031:2011 using [HMAC_DRBG (any)].
FCS_RBG_EXT.1.2 The deterministic RBG shall be seeded by at least one entropy source that
accumulates entropy from [[4 software-based noise source, [0] hardware-based noise source] with a
minimum of [256 bits] of entropy at least equal to the greatest security strength, according to
ISO/IEC 18031:2011 Table C.1 “Security Strength Table for Hash Functions”, of the keys and hashes
that it will generate.
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5.2.4 Cryptographic Protocols (Extended – FCS_SSHS_EXT SSH)
5.2.4.1 FCS_SSHS_EXT.1 SSH Server Protocol
FCS_SSHS_EXT.1 SSH Server Protocol
FCS_SSHS_EXT.1.1 The TSF shall implement the SSH protocol that complies with RFC(s) [4251, 4252,
4253, 4254, 4344, 5656, 6668].
FCS_SSHS_EXT.1.2 The TSF shall ensure that the SSH protocol implementation supports the
following authentication methods as described in RFC 4252: public key-based, [password-based].
FCS_SSHS_EXT.1.3 The TSF shall ensure that, as described in RFC 4253, packets greater than [263K]
bytes in an SSH transport connection are dropped.
FCS_SSHS_EXT.1.4 The TSF shall ensure that the SSH transport implementation uses the following
encryption algorithms and rejects all other encryption algorithms: [aes128-cbc, aes256-cbc, aes128-
ctr, aes256-ctr]3
.
FCS_SSHS_EXT.1.5 The TSF shall ensure that the SSH public-key based authentication
implementation uses [ssh-rsa, rsa-sha2-256, rsa-sha2-512, ecdsa-sha2-nistp256, ecdsa-sha2-
nistp384, ecdsa-sha2-nistp521] as its public key algorithm(s) and rejects all other public key
algorithms.
FCS_SSHS_EXT.1.6 The TSF shall ensure that the SSH transport implementation uses [hmac-sha1,
hmac-sha2-256, hmac-sha2-512] as its MAC algorithm(s) and rejects all other MAC algorithm(s).
FCS_SSHS_EXT.1.7 The TSF shall ensure that [diffie-hellman-group14-sha1, ecdh-sha2-nistp256] and
[ecdh-sha2-nistp384, ecdh-sha2-nistp521] are the only allowed key exchange methods used for the
SSH protocol.
FCS_SSHS_EXT.1.8 The TSF shall ensure that within SSH connections, the same session keys are used
for a threshold of no longer than one hour, and each encryption key is used to protect no more than
one gigabyte of data. After any of the thresholds are reached, a rekey needs to be performed.4
5.3 Identification and Authentication (FIA)
5.3.1 Authentication Failure Management (FIA_AFL)
5.3.1.1 FIA_AFL.1 Authentication Failure Management (Refinement)
FIA_AFL.1 Authentication Failure Management
FIA_AFL.1.1 The TSF shall detect when an Administrator configurable positive integer within [1 to
10] unsuccessful authentication attempts occur related to Administrators attempting to authenticate
remotely using a password.
FIA_AFL.1.2 When the defined number of unsuccessful authentication attempts has been met, the
TSF shall [
prevent the offending remote Administrator from successfully establishing remote session using any
authentication method that involves a password until an Administrator defined time period has
elapsed].
3
Incorporates NIAP TD0189, which makes aes-cbc algorithms selectable while also reflecting the more recent
operation as specified in [NDcPP2.1], which permits assignment of applicable algorithms. Also reflects
Network Device Interpretation #201725, dated 28-Oct-2017.
4
In accordance with TD0475
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ST Application Note
The Security Administrator can select to unlock the account of another administrator who has failed
to authenticate, rather than require the administrator to wait until the delay of an administrator-
configured time period has lapsed before another attempt can be made to authenticate.
5.3.2 Password Management (Extended – FIA_PMG_EXT)
5.3.2.1 FIA_PMG_EXT.1 Password Management
FIA_PMG_EXT.1 Password Management
FIA_PMG_EXT.1.1 The TSF shall provide the following password management capabilities for
administrative passwords:
a) Passwords shall be able to be composed of any combination of upper and lower case letters,
numbers, and the following special characters: [“!”, “@”, “#”, “$”, “%”, “^”, “&”, “*”, “(“, “)”,
[and all other standard ASCII, extended ASCII and Unicode characters]];
b) Minimum password length shall be configurable to between [10] and [20] characters.
5.3.3 User Identification and Authentication (Extended – FIA_UIA_EXT)
5.3.3.1 FIA_UIA_EXT.1 User Identification and Authentication
FIA_UIA_EXT.1 User Identification and Authentication
FIA_UIA_EXT.1.1 The TSF shall allow the following actions prior to requiring the non-TOE entity to
initiate the identification and authentication process:
• Display the warning banner in accordance with FTA_TAB.1;
• [[ICMP echo]].
FIA_UIA_EXT.1.2 The TSF shall require each administrative user to be successfully identified and
authenticated before allowing any other TSF-mediated actions on behalf of that administrative user.
5.3.4 User authentication (FIA_UAU) (Extended – FIA_UAU_EXT)
5.3.4.1 FIA_UAU_EXT.2 Password-based Authentication Mechanism
FIA_UAU_EXT.2 Password-based Authentication Mechanism
FIA_UAU_EXT.2.1 The TSF shall provide a local [password-based] authentication mechanism to
perform local administrative user authentication.
5.3.4.2 FIA_UAU.7 Protected Authentication Feedback
FIA_UAU.7 Protected Authentication Feedback
FIA_UAU.7.1 The TSF shall provide only obscured feedback to the administrative user while the
authentication is in progress at the local console.
5.4 Security Management (FMT)
5.4.1 Management of functions in TSF (FMT_MOF)
5.4.1.1 FMT_MOF.1/ManualUpdate Management of security functions behaviour
FMT_MOF.1/ManualUpdate Management of security functions behaviour
FMT_MOF.1.1/ManualUpdate The TSF shall restrict the ability to enable the functions to perform
manual updates to Security Administrators.
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5.4.1.2 FMT_MOF.1/Services Management of security functions behaviour
FMT_MOF.1/Services Management of security functions behaviour
FMT_MOF.1.1/Services The TSF shall restrict the ability to enable and disable start and stop the
functions services to Security Administrators.
5.4.1.3 FMT_MOF.1/Functions Management of security functions behaviour
FMT_MOF.1/Functions Management of security functions behaviour
FMT_MOF.1.1/Functions The TSF shall restrict the ability to [modify the behaviour of] the functions
[transmission of audit data to an external IT entity, handling of audit data] to Security
Administrators.
5.4.2 Management of TSF Data (FMT_MTD)
5.4.2.1 FMT_MTD.1/CoreData Management of TSF Data
FMT_MTD.1/CoreData Management of TSF Data
FMT_MTD.1.1/CoreData The TSF shall restrict the ability to manage the TSF data to Security
Administrators.
5.4.2.2 FMT_MTD.1/CryptoKeys Management of TSF data
FMT_MTD.1/CryptoKeys Management of TSF data
FMT_MTD.1.1/CryptoKeys The TSF shall restrict the ability to manage the cryptographic keys to
Security Administrators.
5.4.3 Specification of Management Functions (FMT_SMF)
5.4.3.1 FMT_SMF.1 Specification of Management Functions
FMT_SMF.1 Specification of Management Functions
FMT_SMF.1.1 The TSF shall be capable of performing the following management functions:
• Ability to administer the TOE locally and remotely;
• Ability to configure the access banner;
• Ability to configure the session inactivity time before session termination or locking;
• Ability to update the TOE, and to verify the updates using digital signature and [no
other] capability prior to installing those updates;
• Ability to configure the authentication failure parameters for FIA_AFL.1;
[
o Ability to configure audit behaviour;
o Ability to configure thresholds for SSH rekeying;
o Ability to re-enable an Administrator account;
o Ability to set the time which is used for time-stamps;
o Ability to configure the reference identifier for the peer].
]
5.4.4 Security management roles (FMT_SMR)
5.4.4.1 FMT_SMR.2 Restrictions on security roles
FMT_SMR.2 Restrictions on Security Roles
FMT_SMR.2.1 The TSF shall maintain the roles:
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• Security Administrator.
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
• The Security Administrator role shall be able to administer the TOE locally;
• The Security Administrator role shall be able to administer the TOE remotely
are satisfied.
5.5 Protection of the TSF (FPT)
5.5.1 Protection of TSF Data (Extended – FPT_SKP_EXT)
5.5.1.1 FPT_SKP_EXT.1 Protection of TSF Data (for reading of all pre-shared, symmetric
and private keys)
FPT_SKP_EXT.1 Protection of TSF Data (for reading of all pre-shared, symmetric and private keys)
FPT_SKP_EXT.1.1 The TSF shall prevent reading of all pre-shared keys, symmetric keys, and private
keys.
5.5.2 Protection of Administrator Passwords (Extended – FPT_APW_EXT)
5.5.2.1 FPT_APW_EXT.1 Protection of Administrator Passwords
FPT_APW_EXT.1 Protection of Administrator Passwords
FPT_APW_EXT.1.1 The TSF shall store administrative passwords in non-plaintext form.5
FPT_APW_EXT.1.2 The TSF shall prevent the reading of plaintext administrative passwords.6
5.5.3 TSF testing (Extended – FPT_TST_EXT)
5.5.3.1 FPT_TST_EXT.1 TSF Testing (Extended)
FPT_TST_EXT.1 TSF testing
FPT_TST_EXT.1.1 The TSF shall run a suite of the following self-tests [during initial start-up (on
power on)] to demonstrate the correct operation of the TSF: [
• Power on test,
• File integrity test,
• Crypto integrity test,
• Authentication test,
• Algorithm known answer tests7
].
5.5.4 Trusted Update (FPT_TUD_EXT)
5.5.4.1 FPT_TUD_EXT.1 Trusted Update
FPT_TUD_EXT.1 Trusted update
FPT_TUD_EXT.1.1 The TSF shall provide Security Administrators the ability to query the currently
executing version of the TOE firmware/software and [no other TOE firmware/software version].
5
In accordance with TD0483
6
In accordance with TD0483
7
The complete list of algorithm tests is provided in [ECG] “Performing Self-Tests on a Device”.
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FPT_TUD_EXT.1.2 The TSF shall provide Security Administrators the ability to manually initiate
updates to TOE firmware/software and [no other update mechanism].
FPT_TUD_EXT.1.3 The TSF shall provide means to authenticate firmware/software updates to the
TOE using a [digital signature mechanism] prior to installing those updates.
5.5.5 Time stamps (Extended – FPT_STM_EXT))
5.5.5.1 FPT_STM_EXT.1 Reliable Time Stamps
FPT_STM_EXT.1 Reliable Time Stamps
FPT_STM_EXT.1.1 The TSF shall be able to provide reliable time stamps for its own use.
FPT_STM_EXT.1.2 The TSF shall [allow the Security Administrator to set the time].
5.6 TOE Access (FTA)
5.6.1 TSF-initiated Session Locking (Extended – FTA_SSL_EXT)
5.6.1.1 FTA_SSL_EXT.1 TSF-initiated Session Locking
FTA_SSL_EXT.1 TSF-initiated Session Locking
FTA_SSL_EXT.1.1 The TSF shall, for local interactive sessions, [
• terminate the session]
after a Security Administrator-specified time period of inactivity.
5.6.2 Session locking and termination (FTA_SSL)
5.6.2.1 FTA_SSL.3 TSF-initiated Termination (Refinement)
FTA_SSL.3 TSF-initiated Termination
FTA_SSL.3.1: The TSF shall terminate a remote interactive session after a Security Administrator-
configurable time interval of session inactivity.
5.6.2.2 FTA_SSL.4 User-initiated Termination (Refinement)
FTA_SSL.4 User-initiated Termination
FTA_SSL.4.1: The TSF shall allow Administrator-initiated termination of the Administrator’s own
interactive session.
5.6.3 TOE access banners (FTA_TAB)
5.6.3.1 FTA_TAB.1 Default TOE Access Banners (Refinement)
FTA_TAB.1 Default TOE Access Banners
FTA_TAB.1.1: Before establishing an administrative user session the TSF shall display a Security
Administrator-specified advisory notice and consent warning message regarding use of the TOE.
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5.7 Trusted path/channels (FTP)
5.7.1 Trusted Channel (FTP_ITC)
5.7.1.1 FTP_ITC.1 Inter-TSF trusted channel (Refinement)
FTP_ITC.1 Inter-TSF trusted channel
FTP_ITC.1.1 The TSF shall be capable of using [SSH] to provide a trusted communication channel
between itself and authorized IT entities supporting the following capabilities: audit server, [no
other capabilities] that is logically distinct from other communication channels and provides assured
identification of its end points and protection of the channel data from disclosure and detection of
modification of the channel data.
FTP_ITC.1.2 The TSF shall permit the TSF or the authorized IT entities to initiate communication via
the trusted channel.
FTP_ITC.1.3 The TSF shall initiate communication via the trusted channel for [no communication].
5.7.2 Trusted Path (FTP_TRP)
5.7.2.1 FTP_TRP.1/Admin Trusted Path (Refinement)
FTP_TRP.1/Admin Trusted Path
FTP_TRP.1.1/Admin The TSF shall be capable of using [SSH] to provide a communication path
between itself and authorized remote administrators that provides confidentiality and integrity,
that is, logically distinct from other communication paths and provides assured identification of its
end points and protection of the communicated data from disclosure and provides detection of
modification of the channel data.
FTP_TRP.1.2/Admin The TSF shall permit remote Administrators to initiate communication via the
trusted path.
FTP_TRP.1.3/Admin The TSF shall require the use of the trusted path for initial Administrator
authentication and all remote administration actions.
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6 Security Assurance Requirements
34. The TOE security assurance requirements are taken from [NDcPP2.1], together with the
refinements documented in [NDcPP2.1] Section 7, as listed in Table 9 below.
Assurance Class Assurance Component
Security Target (ASE) Conformance claims (ASE_CCL.1)
Extended components definition (ASE_ECD.1)
ST introduction (ASE_INT.1)
Security objectives for the operational environment (ASE_OBJ.1)
Stated security requirements (ASE_REQ.1)
Security Problem Definition (ASE_SPD.1)
TOE summary specification (ASE_TSS.1)
Development (ADV) Basic functional specification (ADV_FSP.1)
Guidance documents (AGD) Operational user guidance (AGD_OPE.1)
Preparative procedures (AGD_PRE.1)
Life cycle support (ALC) Labelling of the TOE (ALC_CMC.1)
TOE CM coverage (ALC_CMS.1)
Tests (ATE) Independent testing – conformance (ATE_IND.1)
Vulnerability assessment (AVA) Vulnerability survey (AVA_VAN.1)
Table 9 Security Assurance Requirements
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7 TOE Summary Specification
7.1 Security Audit
35. Junos OS creates and stores audit records for the following events (the detail of content
recorded for each audit event is detailed in Table 8 (FAU_GEN.1). Auditing is implemented using
syslog.
• Start-up and shut-down of the audit functions
• Administrative login and logout
• Configuration is committed
• Configuration is changed (includes all management activities of TSF data)
• Generating/import of, changing, or deleting of cryptographic keys (see below for more
detail)
• Resetting passwords
• Starting and stopping services
• All use of the identification and authentication mechanisms
• Unsuccessful login attempts limit is met or exceeded
• Any attempt to initiate a manual update
• Result of the update attempt (success or failure)
• The termination of a local/remote/interactive session by the session locking mechanism
• Initiation/termination/failure of the SSH trusted channel to syslog server
• Initiation/termination/failure of the SSH trusted path with Admin
• Application of rules configured with the ‘log’ operation by the packet filtering function
• Indication of packets dropped due to too much network traffic by the packet filtering
function
36. In addition the following management activities of TSF data are recorded:
• configure the access banner;
• configure the session inactivity time before session termination;
• configure the authentication failure parameters for FIA_AFL.1;
• Ability to configure audit behaviour;
• configure the cryptographic functionality;
• configure thresholds for SSH rekeying;
• re-enable an Administrator account;
• set the time which is used for time-stamps.
37. The detail of what events are to be recorded by syslog are determined by the logging level
specified the “level” argument of the “set system syslog” CLI command. To ensure
compliance with the requirements the audit knobs detailed in [ECG] must be configured.
38. As a minimum, Junos OS records the following with each log entry:
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• date and time of the event and/or reaction
• type of event and/or reaction
• subject identity (where applicable)
• the outcome (success or failure) of the event (where applicable).
39. In order to identify the key being operated on, the following details are recorded for all
administrative actions relating to cryptographic keys (generating, importing, changing and
deleting keys):
• SSH session keys– key reference provided by process id
• SSH keys generated for outbound trusted channel to external syslog server
• SSH keys imported for outbound trusted channel to external syslog server
• SSH key configured for SSH public key authentication –the hash of the public key that is
to be used for authentication is recorded in syslog
40. For SSH (ephemeral) session keys the PID is used as the key reference to relate the key
generation and key destruction audit events. The key destruction event is recorded as a session
disconnect event. For example, key generation and key destruction events for a single SSH
session key would be reflected by records similar to the following:
Sep 27 15:09:36 yeti sshd[6529]: Accepted publickey for root from 10.163.18.165 port 45336
ssh2: RSA SHA256:l1vri77TPQ4VaupE2NMYiUXPnGkqBWIgD5vW0OuglGI
…
Sep 27 15:09:40 yeti sshd[6529]: Received disconnect from 10.163.18.165 port 45336:11:
disconnected by user
Sep 27 15:09:40 yeti sshd[6529]: Disconnected from 10.163.18.165 port 45336
41. SSH keys generated for outbound trusted channels are uniquely identified in the audit record by
the public key filename and fingerprint. For example:
Sep 27 23:36:49 yeti ssh-keygen [67873]: Generated SSH key file /root/.ssh/id_rsa.pub with
fingerprint SHA256:g+7lsR7x4lQb1JT8Q3scfb2sOl8lyccojGdmkmw4dwM
42. SSH keys imported for use in establishing outbound trusted channels are uniquely identified in
the audit record by the hash of the key imported and the username importing (to which the key
will be bound).
43. It should be noted that SSH keys used for trusted channels are NOT deleted by mgd when SSH is
de-configured. Hence, the only time SSH keys used for trusted channels are deleted is when a
“request vmhost zeroize” action is performed and the whole appliance is zeroized (which by
definition cannot be recorded).
44. All events recorded by syslog are timestamped. The clock function of Junos OS provides a source
of date and time information for the appliance, used in audit timestamps, which is maintained
using the hardware Time Stamp Counter as the clock source. (FAU_GEN.2, FPT_STM.1)
45. Syslog can be configured to store the audit logs locally (FAU_STG_EXT.1), and optionally to send
them to one or more syslog log servers in real time via Netconf over SSH. (FAU_STG.1,
FMT_MOF.1/Functions). Local audit log are stored in /var/log/ in the underlying filesystem. Only
a Security Administrator can read log files, or delete log and archive files through the CLI
interface or through direct access to the filesystem having first authenticated as a Security
Administrator. The syslogs are automatically deleted locally according to configurable limits on
storage volume. The default maximum size is 1Gb. The default maximum size can be modified by
the user, using the “size” argument for the “set system syslog” CLI command.
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46. The Junos OS defines an active log file and a number of “archive” files (10 by default, but
configurable from 1 to 1000). When the active log file reaches its maximum size, the logging
utility closes the file, compresses it, and names the compressed archive file ‘logfile.0.gz’. The
logging utility then opens and writes to a new active log file. When the new active log file
reaches the configured maximum size, ‘logfile.0.gz’ is renamed ‘logfile.1.gz’, and the active log
file is closed, compressed, and renamed ‘logfile.0.gz’. When the maximum number of archive
files is reached and when the size of the active file reaches the configured maximum size, the
contents of the oldest archived file are deleted so the current active file can be archived.
47. A 1Gb syslog file takes approximately 0.25Gb of storage when archived. Syslog files can acquire
complete storage allocated to /var filesystem, which is platform specific. However, when the
filesystem reaches 92% storage capacity an event is raised to the administrator but the eventd
process (being a privileged process) still can continue using the reserved storage blocks. This
allows the syslog to continue storing events while the administrator frees the storage. If the
administrator does not free the storage in time and the /var filesystem storage becomes
exhausted a final entry is recorded in the log reporting “No space left on device” and logging is
terminated. The appliance continues to operate in the event of exhaustion of audit log storage
space.
7.2 Cryptographic Support
48. Local console access is gained by connecting an RJ-45 cable between the console port on the
appliance and a workstation with a serial connection client.
7.2.1 Algorithms and zeroization
49. All FIPS-approved cryptographic functions implemented by the TOE are implemented in the
following libraries:
• OpenSSL for Junos OS 20.3R1 (based on 1.0.2u) – JUNOS 20.3R1 OpenSSL
• LibMD for Junos OS 20.3R1 (the library is created from same sources as OpenSSL version,
namely 1.0.2p) - JUNOS 20.3R1 LibMD
• Kernel for Junos OS 20.3R1 (based on FreeBSD-11 Stable release) - JUNOS 20.3R1 Kernel
50. The TOE evaluation provides a CAVP validation certificate for all FIPS-approved cryptographic
functions implemented by the TOE. CAVP certificate details are provided in Table 12.
Library Implemented SFRs Supported Function, Usage, Algorithm, Mode, Key
Size
CAVP Certificate
Number
JUNOS 20.3R1 Kernel
OR
JUNOS 20.3R1 OpenSSL
FCS_RBG_EXT.1 Random bit generation with HMAC-DRBG
HMAC-SHA2-256
A869
A871
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JUNOS 20.3R1 OpenSSL FCS_SSHS_EXT.1
FCS_COP.1/DataEncry
ption
FCS_COP.1/Hash
FCS_COP.1/KeyedHash
FCS_COP.1/SigGen
FCS_CKM.1
FCS_CKM.2
SSH AES Data Encryption/Decryption
AES-CBC with key sizes 128 bit and 256
bit
AES-CTR with key sizes 128 bit and 256
bit
SSH Hashing
SHA1, SHA2-256, SHA2-384, SHA2-512
SSH Keyed-hashing
HMAC-SHA1, HMAC-SHA-256, HMAC-
SHA-512
SSH signature generation and verification
using ECDSA:
P-256 w/SHA-256, P-384 w/SHA-384,
P-521 w/SHA-512
SSH Key generation for ECDH
SSH signature generation and verification
using RSA
RSA 2048/3072/4098 w/SHA-256/512
SSH EC Key Agreement including keypair
generation using:
EC (P-256, SHA-256),ED (P-384, SHA-
384), EE (P-521, SHA-512)
A871
FPT_TUD_EXT.1 Trusted Update signature verification using
ECDSA
P-256 w/SHA-256, P-384 w/SHA-384,
P-521 w/SHA-512
JUNOS 20.3R1 LibMD FCS_COP.1/Hash
FPT_APW_EXT.1
FPT_TST_EXT.1
Cryptographic hashing for password
conditioning, password hashing, and self-
testing (verifying integrity of system files)
HMAC-SHA1, HMAC-SHA2-256
As defined in table 14, below.
A873
Table 12 CAVP Certificate Results for Cryptographic Services
51. All random number generation by the TOE is performed in accordance with NIST Special
Publication 800-90 using HMAC_DRBG implemented in the OpenSSL library and kernel library
(FCS_RBG_EXT.1.1). Additionally, SHA (256,512) is implemented in the LibMD library which is
used for password hashing by Junos’ MGD daemon. The appliance is to be operated with FIPS
mode enabled.
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52. The FIPS approved algorithms are applied when the FIPS mode is enabled8
. The relevant FIPS
knobs are specified in [ECG]. (FCS_COP.1/DataEncryption, FCS_COP.1/SigGen, FCS_COP.1/Hash,
FCS_COP.1/KeyedHash, FCS_RBG_EXT.1, FCS_CKM.1, FMT_SMF.1)
53. Asymmetric keys are also generated in accordance with FIPS PUB 186-4 Appendix B.3.3 for RSA
Schemes and Appendix B.4.2 for ECC Schemes for SSH communications. The TOE implements
Diffie-Hellman group 14, using the modulus and generator specified by Section 3 of RFC3526.
(FCS_CKM.2, FCS_CKM.1/ND).
54. The following table relates cryptographic algorithms to the protocols by the TOE. The TOE acts
only as the server for SSH in the supported protocols listed in the following:
Protocol Key Exchange Authentication Encryption
Algorithms
Data Integrity
Algorithms
SSHv2
ecdh-sha2-nistp256
ecdh-sha2-nistp384
ecdh-sha2-nistp521
Diffie-Hellman group 14
(modp 2048)
ssh-rsa
rsa-sha2-256
rsa-sha2-512
ecdsa-sha2-nistp256
ecdsa-sha2-nistp384
ecdsa-sah2-nistp521
AES CTR 128
AES CTR 256
AES CBC 128
AES CBC 256
HMAC-SHA-1
HMAC-SHA-256
HMAC-SHA-512
55. Regardless of the module, the HMAC algorithms use the values specified in the following:
HMAC-SHA-1 HMAC-SHA-256 HMAC-SHA-512
Key Length 160 bits 256 bits 512 bits
Hash function SHA-1 SHA-256 SHA-512
Block Size 512 bits 512 bits 1024 bits
Output MAC 160 bits 256 bits 512 bits
56. Junos OS handles zeroization for all CSP, plaintext secret and private cryptographic keys
according to table below. (FCS_CKM.4).
CSP Description Method
of storage
Storage
location
Zeroization Method
SSH
Private
Host Key
The first time SSH is
configured, the key is
generated. Used to identify
the host.
Plaintext File format
on SDD)
When the appliance is
recommissioned, the config files
(including CSP files such as SSH
keys) are removed using the
“request vmhost zeroize no-
forwarding” option.
Loaded into memory to
complete session
establishment
Plaintext Memory Memory free() operation is
performed by Junos upon
session termination
SSH
Session
Key
Session keys used with SSH,
AES 128, 256, hmac-sha-1,
hmac-sha2-256 or hmac-
sha2-512 key (160, 256 or
512), DH Private Key (2048 or
elliptic curve 256/384/521-
bits)
Plaintext Memory Memory free() operation is
performed by Junos upon
session termination
8
The knob “set system fips level 1” will enforce strict compliance to FIPS and enable restrictions on algorithms
and keys sizes as required by FIPS requirements.
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CSP Description Method
of storage
Storage
location
Zeroization Method
User
Password
Plaintext value as entered by
user
Plaintext as
entered
Processed
in Memory
Memory free() operation is
performed by Junos upon
completion of authentication
Hashed
when
stored
(HMAC-
sha1)
Stored on
disk
When the appliance is
recommissioned, the config files
(including the obfuscated
password) are removed using
the “request vmhost zeroize no-
forwarding” option.
RNG State Internal state and seed key of
RNG
Plaintext Memory Handled by kernel, overwritten
with zero’s at reboot.
57. Junos OS does not provide a CLI interface to permit the viewing of keys. Cryptographic keys are
protected through the enforcement of kernel-level file access rights, limiting access to the
contents of cryptographic key containers to processes with cryptographic rights or shell users
with root permission9
. (FPT_SKP_EXT.1)
7.2.2 Random Bit Generation
58. Junos OS performs random bit generation in accordance with NIST Special Publication 800-90
using HMAC_DRBG, SHA-256. The RBGs in the TOE Routing Engine do not require any
configuration and are seeded from hardware and software sources.
7.2.3 SSH
59. Junos OS supports and enforces Trusted Channels that protect the communications between the
TOE and a remote audit server from unauthorized disclosure or modification. It also supports
Trusted Paths between itself and remote administrators so that the contents of administrative
sessions are protected against unauthorized disclosure or modification. (FTP_ITC.1,
FTP_TRP.1/Admin)
60. Junos OS provides an SSH server to support Trusted Channels using SSHv2 protocol which
ensures the confidentiality and integrity of communication with the remote audit server. Export
of audit information to a secure, remote server is achieved by setting up an event trace monitor
that sends event log messages by using NETCONF over SSH to the remote system event logging
server. The remote audit server initiates the connection. The SSHv2 protocol ensures that the
data transmitted over a SSH session cannot be disclosed or altered by using the encryption and
integrity mechanisms of the protocol with the FIPS cryptographic module. (FTP_ITC.1,
FCS_SSHS_EXT.1)
61. The Junos OS SSH Server also supports Trusted Paths using SSHv2 protocol which ensures the
confidentiality and integrity of user sessions. The encrypted communication path between Junos
OS SSH Server and a remote administrator is provided by the use of an SSH session. Remote
administrators of Junos OS initiate communication to the Junos CLI through the SSH tunnel
created by the SSH session. Assured identification of Junos OS is guaranteed by using public key
based authentication for SSH. The SSHv2 protocol ensures that the data transmitted over a SSH
session cannot be disclosed or altered by using the encryption and integrity mechanisms of the
protocol with the FIPS cryptographic module. (FTP_TRP.1/Admin, FCS_SSHS_EXT.1)
9
Security Administrators do not have root permission in shell.
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62. The Junos OS SSH server is implemented in accordance with RFCs 4251, 4252, 4253, 4254, 4344,
5656 and 6668. Junos OS provides assured identification of the Junos OS appliance though
public key authentication and supports password-based authentication by administrative users
(Security Administrator) for SSH connections. The following table identifies conformance to the
SSH related RFCs:
RFC Summary TOE implementation of Security
RFC 4251 The Secure Shell
(SSH) Protocol
Architecture
Host Keys: The TOE uses an ECDSA Host Key for SSH v2, with a
key size of 256 bits, which is generated on initial setup of the
TOE. It can be de-configured via the CLI and the key will be
deleted and thus unavailable during connection establishment.
This key is randomly generated to be unique to each TOE
instance. The TOE presents the client with its public key and the
client matches this key against its known_hosts list of keys.
When a client connects to the TOE, the client will be able to
determine if the same host key was used in previous
connections, or if the key is different (per the SSHv2 protocol).
Junos OS also supports RSA-based key establishment schemes
with a key size of 2048 bits.
Policy Issues: The TOE implements all mandatory algorithms and
methods. The TOE can be configured to accept public-key based
authentication and/or password-based authentication. The TOE
does not require multiple authentication mechanisms for users.
The TOE allows port forwarding and sessions to clients. The TOE
has no X11 libraries or applications and X11 forwarding is
prohibited.
Confidentiality: The TOE does not accept the “none” cipher.
supports AES-CBC-128, AES-CBC-256, AES-CTR-128, AES-CTR-256
encryption algorithms for protection of data over SSH and uses
keys generated in accordance with “ssh-rsa”, “rsa-sha2-256”,
“rsa-sha2-512”, “ecdsa-sha2-nistp256”, “ecdsa-sha2-nistp384”
or “ecdsa-sha2-nistp521” to perform public-key based device
authentication. For ciphers whose blocksize >= 16, the TOE
rekeys every (2^32-1) bytes. The client may explicitly request a
rekeying event as a valid SSHv2message at any time and the TOE
will honor this request. Re-keying of SSH session keys can be
configured using the sshd_config knob. The data-limit must be
between 51200 and 4294967295 (2^32-1) bytes and the time-
limit must be between 1 and 1440 minutes. In the evaluated
deployment the time-limit must be set within 1 and 60 minutes.
Denial of Service: When the SSH connection is brought down,
the TOE does not attempt to re-establish it.
Ordering of Key Exchange Methods: Key exchange is performed
only using one of the supported key exchange algorithms, which
are ordered as follows: ecdh-sha2-nistp256, ecdh-sha2-nistp384,
ecdh-sha2-nistp521 (all specified in RFC 5656), diffie-hellman-
group14-sha1 (specified in RFC 4253).
Debug Messages: The TOE sshd server does not support debug
messages via the CLI.
End Point Security: The TOE permits port forwarding.
Proxy Forwarding: The TOE permits proxy forwarding.
X11 Forwarding: The TOE does not support X11 forwarding.
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RFC Summary TOE implementation of Security
RFC 4252 The Secure Shell
(SSH) Authentication
Protocol
Authentication Protocol: The TOE does not accept the “none”
authentication method. The TOE implements a timeout period
of 30 seconds for authentication of the SSHv2 protocol and
provides a limit of three failed authentication attempts before
sending a disconnect to the client.
Authentication Requests: The TOE does not accept
authentication if the requested service does not exist. The TOE
does not allow authentication requests for a non-existent
username to succeed – it sends back a disconnect message as it
would for failed authentications and hence does not allow
enumeration of valid usernames. The TOE denies “none”
authentication method and replies with a list of permitted
authentication methods.
Public Key Authentication Method: The TOE supports public key
authentication for SSHv2 session authentication. Authentication
succeeds if the correct private key is used. The TOE does not
require multiple authentications (public key and password) for
users.
Password Authentication Method: The TOE supports password
authentication. Expired passwords are not supported and
cannot be used for authentication.
Host-Based Authentication: The TOE does not support the
configuration of host-based authentication methods.
RFC 4253 The Secure Shell
(SSH) Transport
Layer Protocol
Encryption: The TOE offers the following for encryption of SSH
sessions: aes128-cbc, aes256-cbc, aes128-ctr, and aes256-ctr.
The TOE permits negotiation of encryption algorithms in each
direction. The TOE does not allow the “none” algorithm for
encryption.
Maximum Packet length: Packets greater than 256 Kbytes in an
SSH transport connection are dropped and the connection is
terminated by Junos OS.
Data Integrity: The TOE permits negotiation of HMAC-SHA1 in
each direction for SSH transport.
Key Exchange: The TOE supports diffie-hellman-group14-sha1.
Key Re-Exchange: The TOE performs a re-exchange when
SSH_MSG_KEXINIT is received.
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RFC Summary TOE implementation of Security
RFC 4254 Secure Shell (SSH)
Connection Protocol
Multiple channels: The TOE assigns each channel a number (as
detailed in RFC 4251, see above).
Data transfers: The TOE supports a maximum window size of
256K bytes for data transfer.
Interactive sessions: The TOE only supports interactive sessions
that do NOT involve X11 forwarding.
Forwarded X11 connections: This is not supported in the TOE.
Environment variable passing: The TOE only sets variables once
the server process has dropped privileges.
Starting shells/commands: The TOE supports starting one of
shell, application program or command (only one request per
channel). These will be run in the context of a channel, and will
not halt the execution of the protocol stack.
Window dimension change notices: The TOE will accept
notifications of changes to the terminal size (dimensions) from
the client.
Port forwarding: This is fully supported by the TOE.
RFC4344 Secure Shell (SSH)
Transport Layer
Encryption Modes
Encryption Modes: The TOE implements the recommended
modes aes128-ctr and aes256-ctr (it does not implement the
recommended 3des-ctr, nor does it implement any of the
optional modes).
RFC5656 SSH ECC Algorithm
Integration
ECDH Key Exchange: The support key exchange methods
specified in this RFC are ecdh-sha2-nistp256, ecdh-sha2-
nistp384, or ecdh-sha2-nistp521. The client matches the key
against its known_hosts list of keys.
Hashing: Junos OS supports cryptographic hashing via the SHA-
1, SHA-256, SHA-384 and SHA-512 algorithms, provided it has a
message digest size of either 256 or 512 bits.Required Curves:
All required curves are implemented: ecdh-sha2-nistp256, ecdh-
sha2-nistp384, or ecdh-sha2-nistp521. None of the
Recommended Curves are supported as they are not included in
[NDcPP2.1].
RFC 6668 sha2-Transport Layer
Protocol
Data Integrity Algorithms: Both the recommended and optional
algorithms hmac-sha1, mac-sha2-256 and hmac-sha2-512
(respectively) are implemented for SSH transport.
Table 16 SSH RFC conformance
63. Certificates are stored in non-volatile flash memory. Access to flash memory requires
administrator credentials. A certificate may be loaded via command line
(FMT_MTD.1/CryptoKeys).
7.3 Identification and Authentication
64. Junos OS enforces binding between human users and subjects. The Security Administrator10
is
responsible for provisioning user accounts, and only the Security Administrator can do so.
(FMT_SMR.2, FMT_MTD.1/CoreData)
65. Junos users are configured under “system login user” and are exported to the password
database ‘/var/etc/master.passwd’. A Junos user is therefore an entry in the password
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database. Each entry in the password database has fields corresponding to the attributes of
“system login user”, including username, (obfuscated) password and login class.
66. The internal architecture supporting Authentication includes an active process, associated linked
libraries and supporting configuration data. The Authentication process and library are
• login()
• PAM Library module
67. Following TOE initialization, the login() process is listening for a connection at the local
console. This ‘login’ process can be accessed through either direct connection to the local
console or following successful establishment of a remote management connection over SSH,
when a login prompt is displayed.
68. This login process identifies and authenticates the user using PAM operations. The login process
does two things; it first establishes that the requesting user is whom they claim to be and second
provides them with an interactive Junos Command interactive command line interface (CLI).
69. The SSH daemon supports public key authentication by looking up a public key in an authorized
keys file located in the directory ‘.ssh’ in the user’s home directory (i.e. ‘~/.ssh/’) and this
authentication method will be attempted before any other if the client has a key available
(FIA_UIA_EXT.1). The SSH daemon will ignore the authorized keys file if it or the directory ‘.ssh’
or the user’s home directory are not owned by the user or are writeable by anyone else.
70. For password authentication, login() interacts with a user to request a username and
password to establish and verify the user’s identity. The username entered by the administrator
at the username prompt is reflected to the screen, but no feedback to screen is provided while
the entry made by the administrator at the password prompt until the Enter key is pressed
(FIA_UAU.7). login() uses PAM Library calls for the actual verification of this data. The
password is hashed and compared to the stored value, and success/failure is indicated to
login(), (FIA_UIA_EXT.1). PAM is used in the TOE support authentication management,
account management, session management and password management. Login primarily uses
the session management and password management functionality offered by PAM.
71. The retry-options can be configured to specify the action to be taken if the administrator fails to
enter valid username/password credentials for password authentication when attempting to
authenticate via remote access (FMT_MTD.1/CoreData). The retry-options are applied
following the first failed login attempt for a given username (FIA_AFL.1). The length of delay (5-
10 seconds) after each failed attempt is specified by the backoff-factor, and the increase of the
delay for each subsequent failed attempt is specified by the backoff-threshold (1-3). The tries-
before-disconnect sets the maximum number of times (1-10) the administrator is allowed to
enter a password to attempt to log in to the device through SSH before the connection is
disconnected. The lockout-period sets the amount of time in minutes before the administrator
can attempt to log in to the device after being locked out due to the number of failed login
attempts (1-43,200 minutes). Even when an account is locked for remote access to the TOE, an
administrator is always able to login locally through the serial console and the administrator can
attempt authentication via remote access after the maximum timeout period of 24 hours.
72. The TOE requires users to provide unique identification and authentication data
(passwords/public key) before any access to the system is granted. Prior to authentication, the
only Junos OS managed responses provided to the administrator are (FIA_UAU_EXT.2):
• Negotiation of SSH session
• Display of the access banner
• ICMP echo responses.
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73. Authentication data for fixed password authentication is a case-sensitive, alphanumeric value.
The password has a minimum length of 10 characters and maximum length of 20 characters, and
must contain characters from at least two different character sets (upper, lower, numeric,
punctuation), and can be up to 20 ASCII characters in length (control characters are not
recommended). Any standard ASCII, extended ASCII and Unicode characters can be selected
when choosing a password. (FIA_PMG_EXT.1)
7.4 Security Management
74. Accounts assigned to the Security Administrator role are used to manage Junos OS in accordance
with [NDcPP2.1]. User accounts in the TOE have the following attributes: user identity (user
name), authentication data (password) and role (privilege). The Security Administrator is
associated with the defined login class “security-admin”, which has the necessary permission set
to permit the administrator to perform all tasks necessary to manage Junos OS in accordance
with the requirements of [NDcPP2.1].(FMT_SMR.2)
75. The TOE provides user access either through the system console or remotely over the Trusted
Path using the SSHv2 protocol. Users are required to provide unique identification and
authentication data before any access to the system is granted. (FMT_SMR.2, FMT_SMF.1)
76. The Security Administrator has the capability to:
• Administer the TOE locally via the serial ports on the physical device or remotely over an SSH
connection.
• Initiate a manual update of TOE firmware (FMT_MOF.1/ManualUpdate):
o Query currently executing version of TOE firmware (FPT_TUD_EXT.1)
o Verify update using digital signature (FPT_TUD_EXT.1)
• Manage Functions:
o Transmission of audit data to an external IT entity, including Start/stop and modify
the behaviour of the trusted communication channel to external syslog server
(netconf over SSH) and the trusted path for remote Administrative sessions (SSH)
(FMT_MOF.1/Functions, FMT_MOF.1/Services, FMT_SMF.1)
o Handling of audit data, including setting limits of log file size (FMT_MOF.1/Functions)
• Manage TSF data (FMT_MTD.1/CoreData)
o Create, modify, delete administrator accounts, including configuration of
authentication failure parameters
o Reset administrator passwords
o Re-enable an Administrator account (FIA_AFL.1);
• Manage crypto keys (FMT_MTD.1/CryptoKeys):
o SSH key generation (ecdsa, ssh-rsa)
• Perform management functions (FMT_SMF.1):
o Configure the access banner (FTA_TAB.1)
o Configure the session inactivity time before session termination or locking, including
termination of session when serial console cable is disconnected (FTA_SSL_EXT.1,
FTA_SSL.3)
o Manage cryptographic functionality (FCS_SSHS_EXT.1), including:
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▪ ssh ciphers
▪ hostkey algorithm
▪ key exchange algorithm
▪ hashed message authentication code
▪ thresholds for SSH rekeying
o Set the system time (FPT_STM_EXT.1)
77. Detailed topics on the secure management of Junos OS are discussed in [ECG].
7.5 Protection of the TSF
78. Junos OS runs the following set of self-tests during power on to check the correct operation of
the Junos OS firmware (FPT_TST_EXT.1):
• Power on test – determines the boot-device responds, and performs a memory size check to
confirm the amount of available memory.
• File integrity test –verifies integrity of all mounted signed packages, to assert that system
files have not been tampered with. To test the integrity of the firmware, the fingerprints of
the executables and other immutable files are regenerated and validated against the SHA1
fingerprints contains in the manifest file.
• Crypto integrity test – checks integrity of major CSPs, such as SSH hostkeys and iked
credentials, such as Cas, CERTS, and various keys.
• Authentication error – verifies that veriexec is enabled and operates as expected using
/opt/sbin/kats/cannot-exec.real.
• Kernel, libmd, OpenSSL, QuickSec, SSH – verifies correct output from known answer tests for
appropriate algorithms.
79. Juniper Networks devices run only binaries supplied by Juniper Networks. Within the package,
each Junos OS firmware image includes fingerprints of the executables and other immutable
files. Junos firmware will not execute any binary without a validating registered fingerprint. This
feature protects the system against unauthorized firmware and activity that might compromise
the integrity of the device. These self-tests ensure that only authorized executables are allowed
to run thus ensuring the correct operation of the TOE.
80. In the event of a transiently corrupt state or failure condition, the system will panic; the event
will be logged and the system restarted, having ceased to process network traffic. When the
system restarts, the system boot process does not succeed without passing all applicable self-
tests. This automatic recovery and self-test behavior, is discussed in Chapter 11 of the [ECG].
81. When any self-test fails, the device halts in an error state. No command line input or traffic to
any interface is processed. The device must be power cycled to attempt to return to operation.
This self-test behavior is discussed in [ECG]. (FPT_TST_EXT.1)
82. Locally stored authentication credentials are protected (FPT_APW_EXT.1):
• The password is hashed when stored using hmac-sha1, sha256 or sha512.
• Authentication data for public key-based authentication methods are stored in a directory
owned by the user (and typically with the same name as the user). This directory contains
the files ‘.ssh/authorized_keys’ and ‘.ssh/authorized_keys2’ which are used for SSH public
key authentication.
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83. Security Administrators are able to query the current version of the TOE firmware using the CLI
command “show version” (FPT_TUD_EXT.1) and, if a new version of the TOE firmware is
available, initiate an update of the TOE firmware. Junos OS does not provide partial updates for
the TOE, customers requiring updates must migrate to a subsequent release. Updates are
downloaded and applied manually (there is no automatic updating of the Junos OS). The
installable firmware package containing the Junos OS has a digital signature that is checked
when the Security Administrator attempts to install the package. (FPT_TUD_EXT.1, FMT_SMF.1,
FMT_MOF.1/ManualUpdate)
84. The Junos OS kernel maintains a set of fingerprints (SHA1 digests) for executable files and other
files which should be immutable. The manifest file is signed using the Juniper package signing
key, and is verified by the TOE using the accompanying digital signature. ECDSA (P-256) with
SHA-256 is used for digital signature package verification.
85. The fingerprint loader will only process a manifest for which it can verify the signature. Thus
without a valid digital signature an executable cannot be run. When the command is issued to
install an update, the manifest file for the update is verified and stored, and each
executable/immutable file is verified before it is executed. If any of the fingerprints in an update
are not correctly verified, the TOE uses the last known verified image. (FCS_COP.1/SigGen,
FPT_TUD_EXT.1)
7.6 TOE Access
86. Junos enables Security Administrators to configure an access banner for local and remote SSH
connections provided with the authentication prompt. The banner can provide warnings against
unauthorized access to the secure switch as well as any other information that the Security
Administrator wishes to communicate. (FTA_TAB.1)
87. User sessions (local and remote) can be terminated by users (FTA_SSL.4). The administrative
user can logout of existing CLI and remote SSH sessions by typing logout to exit the session and
the Junos OS makes the current contents unreadable after the admin initiates the termination.
No user activity can take place until the user re-identifies and authenticates.
88. The Security Administrator can set the TOE so that a user session is terminated after a period of
inactivity. (FTA_SSL_EXT.1, FTA_SSL.3) For each user session Junos OS maintains a count of
clock cycles (provided by the system clock) since last activity. The count is reset each time there
is activity related to the user session. When the counter reaches the number of clock cycles
equating to the configured period of inactivity the user session is locked out.
89. Junos OS overwrites the display device and makes the current contents unreadable after the
local interactive session is terminated due to inactivity, thus disabling any further interaction
with the TOE. This mechanism is the inactivity timer for administrative sessions. The Security
Administrator can configure this inactivity timer on administrative sessions after which the
session will be logged out.
7.7 Trusted path/Trusted Channels
90. The TOE supports SSH v2 for trusted channel implementation to Syslog server. The TOE supports
SSH v2 ( remote CLI ) for secure remote administration of the TOE.
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8 Glossary
AES Advanced Encryption Standard
ANSI American National Standards Institute
API Application Program Interface
cPP collaborative Protection Profile
CCM Counter with Cipher Block Chaining-Message Authentication Code
CFP C Form-factor Pluggable
CSP Critical security parameter
DH Diffie Hellman
EAL Evaluation Assurance Level
ECC Elliptic Curve Cryptography
ECDSA Elliptic Curve Digital Signature Algorithm
EP Extended Package, defined in [CC1]
ESP Encapsulating Security Payload
FFC Finite Field Cryptography
FIPS Federal Information Processing Standard
HMAC Keyed-Hash Authentication Code
I&A Identification and Authentication
ID Identification
IETF Internet Engineering Task Force
IP Internet Protocol
IPv6 Internet Protocol Version 6
ISO International Organization for Standardization
IT Information Technology
Junos Juniper Operating System
MIC Modular Interface Cards
MPC Modular Port Concentrator
MS-MPC MultiServices Modular Port Concentrator
NAT Network Address Translation
NDcPP Network Device collaborative Protection Profile
NTP Network Time Protocol
OSI Open Systems Interconnect
OSP Organizational Security Policy
PAM Pluggable Authentication Module
PFE Packet Forwarding Engine
PIC/PIM Physical Interface Card/Module
PKI Public Key Infrastructure
POE Power over Ethernet
PP Protection Profile
PRNG Pseudo Random Number Generator
RE Routing Engine
RFC Request for Comment
RNG Random Number Generator
RSA Rivest, Shamir, Adelman
SA Security Association
SFP Small Form-factor Pluggable
SFR Security Functional Requirement
SHA Secure Hash Algorithm
SNMP Simple Network Management Protocol
SSH Secure Shell
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SSL Secure Sockets Layer
ST Security Target
TOE Target of Evaluation
TSF TOE Security Functionality
TSFI TSF interfaces
UDP User Datagram Protocol