High Sec Labs
FH10N-4
Firmware Version 40404-0E7
Security Target
Doc No: 2149-001-D102A6B
Version: 1.3
27 February 2025
High Sec Labs Ltd.
29 HaEshel St
Caesarea,
Israel 3079510
Prepared by:
EWA-Canada, An Intertek Company
1223 Michael Street North, Suite 200
Ottawa, Ontario, Canada
K1J 7T2
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CONTENTS
1 SECURITY TARGET INTRODUCTION.............................................1
1.1 DOCUMENT ORGANIZATION........................................................... 1
1.2 SECURITY TARGET REFERENCE....................................................... 1
1.3 TOE REFERENCE........................................................................... 2
1.4 TOE OVERVIEW............................................................................ 2
TOE Environment ...........................................................................3
1.5 TOE DESCRIPTION ....................................................................... 3
USB Filter Evaluated Configuration ...................................................4
Physical Scope ...............................................................................4
Logical Scope.................................................................................5
2 CONFORMANCE CLAIMS...............................................................6
2.1 COMMON CRITERIA CONFORMANCE CLAIM ...................................... 6
2.2 PROTECTION PROFILE CONFORMANCE CLAIM ................................... 6
2.3 PACKAGE CLAIM........................................................................... 7
2.4 CONFORMANCE RATIONALE ........................................................... 7
3 SECURITY PROBLEM DEFINITION................................................8
3.1 THREATS .................................................................................... 8
3.2 ORGANIZATIONAL SECURITY POLICIES ........................................... 9
3.3 ASSUMPTIONS............................................................................. 9
4 SECURITY OBJECTIVES..............................................................10
4.1 SECURITY OBJECTIVES FOR THE TOE ............................................ 10
4.2 SECURITY OBJECTIVES FOR THE OPERATIONAL ENVIRONMENT......... 13
4.3 SECURITY OBJECTIVES RATIONALE............................................... 14
5 EXTENDED COMPONENTS DEFINITION......................................18
6 SECURITY REQUIREMENTS ........................................................19
6.1 CONVENTIONS........................................................................... 19
6.2 SECURITY FUNCTIONAL REQUIREMENTS........................................ 19
User Data Protection (FDP)............................................................20
Protection of the TSF (FPT)............................................................23
6.3 SECURITY ASSURANCE REQUIREMENTS......................................... 24
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6.4 SECURITY REQUIREMENTS RATIONALE.......................................... 24
Security Functional Requirements Rationale.....................................24
Dependency Rationale ..................................................................25
Security Assurance Requirements Rationale.....................................25
7 TOE SUMMARY SPECIFICATION.................................................26
7.1 USER DATA PROTECTION ............................................................ 26
System Controller ........................................................................26
Keyboard and Mouse Functionality..................................................27
7.2 PROTECTION OF THE TSF ............................................................ 28
No Access to TOE .........................................................................28
Anti-tampering Functionality..........................................................28
TSF Testing .................................................................................29
8 TERMINOLOGY AND ACRONYMS ................................................30
8.1 TERMINOLOGY........................................................................... 30
8.2 ACRONYMS................................................................................ 30
9 REFERENCES..............................................................................32
ANNEX A – LETTER OF VOLATILITY ........................................................1
LIST OF TABLES
Table 1 – Non-TOE Hardware and Software................................................. 3
Table 2 – TOE Isolator Device and Features ................................................ 4
Table 3 – Logical Scope of the TOE ............................................................ 5
Table 4 – Applicable Technical Decisions ..................................................... 7
Table 5 – Threats.................................................................................... 9
Table 6 – Assumptions............................................................................. 9
Table 7 – Security Objectives for the TOE ................................................. 13
Table 8 – Security Objectives for the Operational Environment..................... 14
Table 9 – Security Objectives Rationale .................................................... 17
Table 10 – Functional Families of Extended Components ............................. 18
Table 11 – Summary of Security Functional Requirements........................... 20
Table 12 – Security Assurance Requirements............................................. 24
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Table 13 – Functional Requirement Dependencies ...................................... 25
Table 14 – Terminology ......................................................................... 30
Table 15 – Acronyms............................................................................. 31
Table 16 – References ........................................................................... 32
LIST OF FIGURES
Figure 1 – Simplified Filter Diagram for a HID Filter...................................... 3
Figure 2 – USB Filter Evaluated Configuration.............................................. 4
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1 SECURITY TARGET INTRODUCTION
This Security Target (ST) defines the scope of the evaluation in terms of the
assumptions made, the intended environment for the Target of Evaluation
(TOE), the Information Technology (IT) security functional and assurance
requirements to be met, and the level of confidence (evaluation assurance level)
to which it is asserted that the TOE satisfies its IT security requirements. This
document forms the baseline for the Common Criteria (CC) evaluation.
1.1 DOCUMENT ORGANIZATION
Section 1, ST Introduction, provides the Security Target reference, the Target
of Evaluation reference, the TOE overview and the TOE description.
Section 2, Conformance Claims, describes how the ST conforms to the
Common Criteria, Protection Profile (PP) and PP Module.
Section 3, Security Problem Definition, describes the expected environment
in which the TOE is to be used. This section defines the set of threats that are
relevant to the secure operation of the TOE, organizational security policies with
which the TOE must comply, and secure usage assumptions applicable to this
analysis.
Section 4, Security Objectives, defines the set of security objectives to be
satisfied by the TOE and by the TOE operating environment in response to the
problem defined by the security problem definition.
Section 5, Extended Components Definition, defines the extended
components which are then detailed in Section 6.
Section 6, Security Requirements, specifies the security functional and
assurance requirements that must be satisfied by the TOE and the IT
environment.
Section 7, TOE Summary Specification, describes the security functions that
are included in the TOE to enable it to meet the IT security functional
requirements.
Section 8 Terminology and Acronyms, defines the acronyms and
terminology used in this ST.
Section 9 References, provides a list of documents referenced in this ST.
1.2 SECURITY TARGET REFERENCE
ST Title: High Sec Labs FH10N-4 Firmware Version 40404-0E7
Security Target
ST Version: 1.3
ST Date: 27 February 2025
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1.3 TOE REFERENCE
TOE Identification: High Sec Labs FH10N-4 Firmware Version 40404-0E7
TOE Developer: High Sec Labs Ltd.
TOE Type: Peripheral Sharing Device (Other Devices and
Systems)
1.4 TOE OVERVIEW
The High Sec Labs (HSL) Secure Universal Serial Bus (USB) Human Interface
Device (HID) filter (FH10N-4) is connected between a computer and a USB
keyboard/mouse to prevent the exploitation of data leakage.
The following security features are provided by the HSL FH10N-4 USB HID Filter:
• Keyboard and Mouse Security
• The keyboard and mouse are isolated by dedicated, USB device
emulation for each computer
• One-way, peripheral-to-computer data flow is enforced through
unidirectional optical data diodes
• Communication from computer-to-keyboard/mouse is blocked
• Non HID (Human Interface Device) data transactions are blocked
• Hardware Anti-Tampering
• Special holographic tampering evident labels on the product’s
enclosure provide a clear visual indication if the product has been
opened or compromised
The HSL USB HID filter device uses an isolated microcontroller to emulate
connected peripherals in order to ensure one-way peripheral to computer data
flow.
Figure 1 is a simplified block diagram showing the TOE keyboard and mouse
data path for two ports. A Host Emulator (HE) communicates with the user
keyboard via the USB protocol. The Host Emulator converts user keystrokes into
unidirectional serial data. An isolated Device Emulator (DE) is connected to the
data diode on one side and to the computer on the other side. Each key stroke
or mouse action is converted by the DE into a bi-directional stream to
communicate with the computer.
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Figure 1 – Simplified Filter Diagram for a HID Filter
The TOE is a combined software and hardware TOE. A mapping showing the
applicable Security Functional Requirements (SFRs) is included in Annex B.
TOE Environment
The following components are required for operation of the TOE in the evaluated
configuration.
Component Description
Connected Computer General purpose computer
Keyboard General purpose USB keyboard
Mouse General purpose USB mouse
HSL KVM Cables USB Type-A to USB Type-B (keyboard and mouse)
Table 1 – Non-TOE Hardware and Software
1.5 TOE DESCRIPTION
The TOE includes the following device type:
• HID USB Filter FH10N-4
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USB Filter Evaluated Configuration
Figure 2 – USB Filter Evaluated Configuration
The HID USB Filter is connected to keyboard and mouse peripherals, and to the
appropriate USB ports on the computer.
Physical Scope
The TOE consists of the following device.
Product
Description
Part
Number
Model
Tamper
Evident
labels
Active
Anti-
Tampering
Number of
supported
connected
computers
USB HID Filter CGA19436 FH10N-4 Yes No 1
Table 2 – TOE Isolator Device and Features
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1.5.2.1 TOE Delivery
The TOE, together with its corresponding cables are delivered to the customer
via trusted carrier, such as Fed-Ex, that provides a tracking service for all
shipments.
1.5.2.2 TOE Guidance
The TOE includes the following guidance documentation:
• HSL Quick Installation Guide HSL-s USB eLock Solution, HDC20403 Rev
1.1.
Guidance may be downloaded from the High Sec Labs website
(https://highseclabs.com/quick-start-guides/) in .pdf format.
The following guidance is available upon request by emailing
support@highseclabs.com:
• High Sec Labs FH10N-4 Firmware Version 40404-0E7 Common Criteria
Guidance Supplement, Version 0.4
Logical Scope
The logical boundary of the TOE includes all interfaces and functions within the
physical boundary. The logical boundary of the TOE may be broken down by the
security function classes described in Section 6. Table 3 summarizes the logical
scope of the TOE.
Functional Classes Description
User Data Protection The TOE enforces unidirectional data flow for keyboard and
mouse. The TOE ensures that only authorized peripheral
devices may be used.
Protection of the TSF1
The TOE ensures a secure state in the case of failure,
provides only restricted access, and performs self-testing.
The TOE provides passive detection of physical attack.
Table 3 – Logical Scope of the TOE
1
TOE Security Functionality
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2 CONFORMANCE CLAIMS
2.1 COMMON CRITERIA CONFORMANCE CLAIM
This Security Target claims to be conformant to Version 3.1 of Common Criteria
for Information Technology Security Evaluation according to:
• Common Criteria for Information Technology Security Evaluation, Part 1:
Introduction and General Model; CCMB-2017-04-001, Version 3.1,
Revision 5, April 2017
• Common Criteria for Information Technology Security Evaluation, Part 2:
Security Functional Components; CCMB-2017-04-002, Version 3.1,
Revision 5, April 2017
• Common Criteria for Information Technology Security Evaluation, Part 3:
Security Assurance Components CCMB-2017-04-003, Version 3.1,
Revision 5, April 2017
As follows:
• CC Part 2 extended
• CC Part 3 conformant
The Common Methodology for Information Technology Security Evaluation,
Version 3.1, Revision 5, April 2017 has been taken into account.
2.2 PROTECTION PROFILE CONFORMANCE
CLAIM
This ST claims exact conformance with the National Information Assurance
Partnership (NIAP) PP‐Configuration for Peripheral Sharing Device and
Keyboard/Mouse Devices, 19 July 2019 [CFG_PSD‐KM_V1.0].
This PP-Configuration includes the following components:
• Base-PP: Protection Profile for Peripheral Sharing Device, Version 4.0
[PP_PSD_V4.0]
• PP-Module: PP-Module for Keyboard/Mouse Devices, Version 1.0
[MOD_KM_V1.0].
TD Name PP affected Relevant
Y/N
TD0507 Clarification on USB plug type [MOD_KM_V1.0] Y
TD0518 Typographical errors in dependency
Table
[PP_PSD_V4.0] N
FPT_STM.1
is not
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claimed in
the ST
TD0583 FPT_PHP.3 modified for remote
controllers
[PP_PSD_V4.0] Y
TD0593 Equivalency Arguments for PSD [MOD_KM_V1.0 Y
TD0804 Clarification regarding Extenders in
PSD Evaluations
[PP_PSD_V4.0] N
TD0844 Addition of Assurance Package for
Flaw Remediation V1.0 Conformance
Claim
[PP_PSD_V4.0] N
Table 4 – Applicable Technical Decisions
2.3 PACKAGE CLAIM
This Security Target does not claim conformance with any Package.
2.4 CONFORMANCE RATIONALE
The TOE USB HID Filter is inherently consistent with the Compliant Targets of
Evaluation described in the [PP_PSD_V4.0] and in the PP module listed in
Section2.2, and with the PP‐Configuration for Peripheral Sharing Device and
Keyboard/Mouse Devices [CFG_PSD‐KM_V1.0].
The security problem definition, statement of security objectives and statement
of security requirements in this ST conform exactly to the security problem
definition, statement of security objectives and statement of security
requirements contained in [PP_PSD_V4.0] and the module listed in Section 2.2
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3 SECURITY PROBLEM DEFINITION
3.1 THREATS
Table 5 lists the threats described in Section 3.1 of the [PP_PSD_V4.0].
Mitigation to the threats is through the objectives identified in Section 4.1,
Security Objectives for the TOE.
Threat Description
T.DATA_LEAK A connection via the PSD2
between one or more
computers may allow unauthorized data flow through
the PSD or its connected peripherals.
T.SIGNAL_LEAK A connection via the PSD between one or more
computers may allow unauthorized data flow through
bit‐by‐bit signaling.
T.RESIDUAL_LEAK A PSD may leak (partial, residual, or echo) user data
between the intended connected computer and another
unintended connected computer.
T.UNINTENDED_USE A PSD may connect the user to a computer other than
the one to which the user intended to connect.
T.UNAUTHORIZED_DEVICES The use of an unauthorized peripheral device with a
specific PSD peripheral port may allow unauthorized
data flows between connected devices or enable an
attack on the PSD or its connected computers.
T.LOGICAL_TAMPER An attached device (computer or peripheral) with
malware, or otherwise under the control of a
malicious user, could modify or overwrite code or
data stored in the PSD’s volatile or non‐volatile
memory to allow unauthorized information flows.
T.PHYSICAL_TAMPER A malicious user or human agent could physically
modify the PSD to allow unauthorized information
flows.
T.REPLACEMENT A malicious human agent could replace the PSD
during shipping, storage, or use with an alternate
device that does not enforce the PSD security
policies.
2
Peripheral Sharing Device
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Threat Description
T.FAILED Detectable failure of a PSD may cause an
unauthorized information flow or weakening of PSD
security functions.
Table 5 – Threats
3.2 ORGANIZATIONAL SECURITY POLICIES
There are no Organizational Security Policies applicable to this TOE.
3.3 ASSUMPTIONS
The assumptions required to ensure the security of the TOE are listed in Table 6.
Assumptions Description
A.NO_TEMPEST Computers and peripheral devices connected to the
PSD are not TEMPEST approved.
The TSF may or may not isolate the ground of the
keyboard and mouse computer interfaces (the USB
ground). The Operational Environment is assumed not
to support TEMPEST red‐black ground isolation.
A.PHYSICAL The environment provides physical security
commensurate with the value of the TOE and the data
it processes and contains.
A.NO_WIRELESS_DEVICES The environment includes no wireless peripheral
devices.
A.TRUSTED_ADMIN PSD Administrators and users are trusted to follow and
apply all guidance in a trusted manner.
A.TRUSTED_CONFIG Personnel configuring the PSD and its operational
environment follow the applicable security
configuration guidance.
A.USER_ALLOWED_ACCESS All PSD users are allowed to interact with all
connected computers. It is not the role of the PSD to
prevent or otherwise control user access to connected
computers. Computers or their connected network
shall have the required means to authenticate the user
and to control access to their various resources.
Table 6 – Assumptions
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4 SECURITY OBJECTIVES
The purpose of the security objectives is to address the security concerns and to
show which security concerns are addressed by the TOE, and which are
addressed by the environment. Threats may be addressed by the TOE or the
security environment or both. Therefore, the CC identifies two categories of
security objectives:
• Security objectives for the TOE
• Security objectives for the environment
4.1 SECURITY OBJECTIVES FOR THE TOE
This section identifies and describes the security objectives that are to be
addressed by the TOE, and traces each Security Functional Requirement (SFR)
back to a security objective of the TOE.
Security Objective Description
O.COMPUTER
_INTERFACE
_ISOLATION
The PSD shall prevent unauthorized data flow to ensure that
the PSD and its connected peripheral devices cannot be
exploited in an attempt to leak data. The TOE‐Computer
interface shall be isolated from all other PSD‐Computer
interfaces while TOE is powered.
Addressed by:
MOD_KM FDP_APC_EXT.1/KM, FDP_FIL_EXT.1/KM,
FDP_PDC_EXT.1, FDP_RDR_EXT.1
O.COMPUTER
_INTERFACE
_ISOLATION
_TOE_UNPOWERED
The PSD shall not allow data to transit a PSD‐Computer
interface while the PSD is unpowered.
Addressed by:
MOD_KM FDP_APC_EXT.1/KM, FDP_FIL_EXT.1/KM,
FDP_PDC_EXT.1, FDP_RDR_EXT.1
O.USER_DATA
_ISOLATION
The PSD shall route user data, such as keyboard entries, only
to the computer selected by the user. The PSD shall provide
isolation between the data flowing from the peripheral device
to the selected computer and any non‐selected computer.
Addressed by:
MOD_KM FDP_APC_EXT.1/KM, FDP_FIL_EXT.1/KM,
FDP_PDC_EXT.1, FDP_RDR_EXT.1
O.NO_USER
_DATA_RETENTION
The PSD shall not retain user data in non‐volatile memory
after power up or, if supported, factory reset.
Addressed by:
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Security Objective Description
PP_PSD FDP_RIP_EXT.1
MOD_KM FDP_RIP.1/KM
O.NO_OTHER
_EXTERNAL
_INTERFACES
The PSD shall not have any external interfaces other than
those implemented by the TSF.
Addressed by:
PP_PSD FDP_PDC_EXT.1
O.LEAK
_PREVENTION
_SWITCHING
The PSD shall ensure that there are no switching mechanisms
that allow signal data leakage between connected computers.
Addressed by:
PP_PSD FDP_SWI_EXT.1
O.AUTHORIZED
_USAGE
The TOE shall explicitly prohibit or ignore unauthorized
switching mechanisms, either because it supports only one
connected computer or because it allows only authorized
mechanisms to switch between connected computers.
Authorized switching mechanisms shall require express user
action restricted to console buttons, console switches, console
touch screen, wired remote control, and peripheral devices
using a guard. Unauthorized switching mechanisms include
keyboard shortcuts, also known as “hotkeys,” automatic port
scanning, control through a connected computer, and control
through keyboard shortcuts. Where applicable, the results of
the switching activity shall be indicated by the TSF so that it
is clear to the user that the switching mechanism was
engaged as intended.
A conformant TOE may also provide a management function
to configure some aspects of the TSF. If the TOE provides this
functionality, it shall ensure that whatever management
functions it provides can only be performed by authorized
administrators and that an audit trail of management
activities is generated.
Addressed by:
PP_PSD FDP_SWI_EXT.1
MOD_KM FDP_FIL_EXT.1/KM
O.PERIPHERAL
_PORTS_ISOLATION
The PSD shall ensure that data does not flow between
peripheral devices connected to different PSD interfaces.
Addressed by:
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Security Objective Description
PP_PSD FDP_APC_EXT.1
MOD_KM FDP_APC_EXT.1/KM, FDP_FIL_EXT.1/KM,
FDP_PDC_EXT.1, FDP_RDR_EXT.1
O.REJECT
_UNAUTHORIZED
_PERIPHERAL
The PSD shall reject unauthorized peripheral device types and
protocols.
Addressed by:
PP_PSD FDP_PDC_EXT.1
MOD_KM FDP_APC_EXT.1/KM, FDP_FIL_EXT.1/KM,
FDP_PDC_EXT.1, FDP_RDR_EXT.1,
FDP_SWI_EXT.3, FDP_PDC_EXT.2/KM
O.REJECT
_UNAUTHORIZED
_ENDPOINTS
The PSD shall reject unauthorized peripheral devices
connected via a Universal Serial Bus (USB) hub.
Addressed by:
PP_PSD FDP_PDC_EXT.1
MOD_KM FDP_APC_EXT.1/KM, FDP_FIL_EXT.1/KM,
FDP_PDC_EXT.1, FDP_RDR_EXT.1
O.NO_TOE_ACCESS The PSD firmware, software, and memory shall not be
accessible via its external ports.
Addressed by:
PP_PSD FPT_NTA_EXT.1
O.TAMPER
_EVIDENT
_LABEL
The PSD shall be identifiable as authentic by the user and the
user must be made aware of any procedures or other such
information to accomplish authentication. This feature must
be available upon receipt of the PSD and continue to be
available during the PSD deployment. The PSD shall be
labeled with at least one visible unique identifying tamper‐
evident marking that can be used to authenticate the device.
The PSD manufacturer must maintain a complete list of
manufactured PSD articles and their respective identification
markings’ unique identifiers.
Addressed by:
PP_PSD FPT_PHP.1
O.ANTI_TAMPERING The PSD shall be physically enclosed so that any attempts to
open or otherwise access the internals or modify the
connections of the PSD would be evident, and optionally
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Security Objective Description
thwarted through disablement of the TOE. Note: This applies
to a wired remote control as well as the main chassis of the
PSD.
Addressed by:
PP_PSD FPT_PHP.1
O.SELF_TEST The PSD shall perform self‐tests following power up or
powered reset.
Addressed by:
PP_PSD FPT_TST.1
O.SELF_TEST
_FAIL_TOE
_DISABLE
The PSD shall enter a secure state upon detection of a critical
failure.
Addressed by:
PP_PSD FPT_FLS_EXT.1, FPT_TST_EXT.1
O.SELF_TEST
_FAIL_INDICATION
The PSD shall provide clear and visible user indications in the
case of a self‐test failure.
Addressed by:
PP_PSD FPT_TST_EXT.1
O.EMULATED_INPUT The TOE shall emulate the keyboard and/or mouse functions
from the TOE to the connected computer.
Addressed by:
MOD_KM FDP_PDC_EXT.2/KM, FDP_PDC_EXT.3/KM
O.UNIDIRECTIONAL
_INPUT
The TOE shall enforce unidirectional keyboard and/or mouse
device’s data flow from the peripheral device to only the
selected computer.
Addressed by:
MOD_KM FDP_UDF_EXT.1/KM
Table 7 – Security Objectives for the TOE
4.2 SECURITY OBJECTIVES FOR THE
OPERATIONAL ENVIRONMENT
This section identifies and describes the security objectives that are to be
addressed by the IT environment or by non-technical or procedural means.
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Security Objective Description
OE.NO_TEMPEST The operational environment will not use TEMPEST
approved equipment.
OE.PHYSICAL The operational environment will provide physical
security, commensurate with the value of the PSD
and the data that transits it.
OE.NO_WIRELESS_DEVICES The operational environment will not include
wireless keyboards, mice, audio, user
authentication, or video devices.
OE.TRUSTED_ADMIN The operational environment will ensure that trusted
PSD Administrators and users are appropriately
trained.
OE.TRUSTED_CONFIG The operational environment will ensure that
administrators configuring the PSD and its
operational environment follow the applicable
security configuration guidance.
Table 8 – Security Objectives for the Operational Environment
4.3 SECURITY OBJECTIVES RATIONALE
The security objectives rationale describes how the assumptions and threats
map to the security objectives.
Threat or
Assumption
Security
Objective(s)
Rationale
T.DATA_LEAK O.COMPUTER
_INTERFACE
_ISOLATION
Isolation of computer interfaces
prevents data from leaking between
them without authorization.
O.COMPUTER
_INTERFACE
_ISOLATION
_TOE_UNPOWERED
Maintaining interface isolation while
the TOE is in an unpowered state
ensures that data cannot leak
between computer interfaces.
O.USER_DATA
_ISOLATION
The TOE’s routing of data only to the
selected computer ensures that it will
not leak to any others.
O.NO_OTHER
_EXTERNAL
_INTERFACES
The absence of additional external
interfaces ensures that there is no
unexpected method by which data
can be leaked.
O.PERIPHERAL_PORTS
_ISOLATION
Isolation of peripheral ports prevents
data from leaking between them
without authorization.
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Threat or
Assumption
Security
Objective(s)
Rationale
O.UNIDIRECTIONAL
_INPUT
The TOE’s enforcement of
unidirectional input for
keyboard/mouse data prevents
leakage of computer data through a
connected peripheral interface.
T.SIGNAL_LEAK O.COMPUTER
_INTERFACE
_ISOLATION
Isolation of computer interfaces
prevents data leakage through bit‐
wise signaling because there is no
mechanism by which the signal data
can be communicated.
O.NO_OTHER
_EXTERNAL
_INTERFACES
The absence of additional external
interfaces ensures that there is no
unexpected method by which data
can be leaked through bitwise
signaling.
O.LEAK_PREVENTION
_SWITCHING
The TOE’s use of switching methods
that are not susceptible to signal
leakage helps mitigate the signal leak
threat.
O.UNIDIRECTIONAL
_INPUT
The TOE’s enforcement of
unidirectional input for
keyboard/mouse data prevents
leakage of computer data through bit‐
by‐bit signaling to a connected
peripheral interface.
T.RESIDUAL
_LEAK
O.NO_USER_DATA
_RETENTION
The TOE’s lack of data retention
ensures that a residual data leak is
not possible.
T.UNINTENDED
_USE
O.AUTHORIZED
_USAGE
The TOE’s support for only switching
mechanisms that require explicit user
action to engage ensures that a user
has sufficient information to avoid
interacting with an unintended
computer.
T.UNAUTHORIZED
_DEVICES
O.REJECT
_UNAUTHORIZED
_ENDPOINTS
The TOE’s ability to reject
unauthorized endpoints mitigates the
threat of unauthorized devices being
used to communicate with connected
computers.
O.REJECT
_UNAUTHORIZED
_PERIPHERAL
The TOE’s ability to reject
unauthorized peripherals mitigates
the threat of unauthorized devices
being used to communicate with
connected computers.
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Threat or
Assumption
Security
Objective(s)
Rationale
O.EMULATED_INPUT The TOE’s emulation of
keyboard/mouse data input ensures
that a connected computer will only
receive this specific type of data
through a connected peripheral.
T.LOGICAL
_TAMPER
O.NO_TOE_ACCESS The TOE’s prevention of logical
access to its firmware, software, and
memory mitigates the threat of
logical tampering.
O.EMULATED_INPUT The TOE’s emulation of
keyboard/mouse data input prevents
logical tampering of the TSF ensuring
that only known inputs to it are
supported.
T.PHYSICAL
_TAMPER
O.ANTI_TAMPERING The TOE mitigates the threat of
physical tampering through use of an
enclosure that provides tamper
detection functionality.
O.TAMPER_EVIDENT
_LABEL
The TOE mitigates the threat of
physical tampering through use of
tamper evident labels that reveal
physical tampering attempts.
T.REPLACEMENT O.TAMPER_EVIDENT
_LABEL
The TOE’s use of a tamper evident
label that provides authenticity of the
device mitigates the threat that it is
substituted for a replacement device
during the acquisition process.
T.FAILED O.SELF_TEST The TOE mitigates the threat of
failures leading to compromise of
security functions through self‐tests
of its own functionality.
O.SELF_TEST_FAIL
_TOE_DISABLE
The TOE mitigates the threat of
failures leading to compromise of
security functions by disabling all
data flows in the event a failure is
detected.
O.SELF_TEST_FAIL
_INDICATION
The TOE mitigates the threat of
failures leading to compromise of
security functions by providing users
with a clear indication when it is in a
failure state and should not be
trusted.
A.NO_TEMPEST OE.NO_TEMPEST If the TOE’s operational environment
does not include TEMPEST approved
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Threat or
Assumption
Security
Objective(s)
Rationale
equipment, then the assumption is
satisfied.
A.NO_PHYSICAL OE.PHYSICAL If the TOE’s operational environment
provides physical security, then the
assumption is satisfied.
A.NO_WIRELESS_DE
VICES
OE.NO_WIRELESS_DEVI
CES
If the TOE’s operational environment
does not include wireless peripherals,
then the assumption is satisfied.
A.TRUSTED_ADMIN OE.TRUSTED_ADMIN If the TOE’s operational environment
ensures that only trusted
administrators will manage the TSF,
then the assumption is satisfied.
A.TRUSTED_CONFIG OE.TRUSTED_CONFIG If TOE administrators follow the
provided security configuration
guidance, then the assumption is
satisfied.
A.USER_ALLOWED_A
CCESS
OE.PHYSICAL If the TOE’s operational environment
provides physical access to connected
computers, then the assumption is
satisfied.
Table 9 – Security Objectives Rationale
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5 EXTENDED COMPONENTS DEFINITION
The extended components definition is presented in Appendix C of the Protection
Profile for Peripheral Sharing Device [PP_PSD_V4.0] and in the module for
keyboard/mouse devices [MOD_KM_V1.0].
The families to which these components belong are identified in the following
table:
Functional
Class
Functional Families Protection Profile
Modules
User Data Protection
(FDP)
FDP_APC_EXT Active PSD Connections [PP_PSD_V4.0]
FDP_FIL_EXT Device Filtering [PP_PSD_V4.0]
[MOD_KM_V1.0]
FDP_PDC_EXT Peripheral Device Connection [MOD_KM_V1.0]
FDP_RDR_EXT Re-Enumeration Device
Rejection
[MOD_KM_V1.0]
FDP_RIP_EXT Residual Information Protection [PP_PSD_V4.0]
FDP_UDF_EXT Unidirectional Data Flow [MOD_KM_V1.0]
Protection of the TSF
(FPT)
FPT_FLS_EXT Failure with Preservation of
Secure State
[PP_PSD_V4.0]
FPT_NTA_EXT No Access to TOE [PP_PSD_V4.0]
FPT_TST_EXT TSF Testing [PP_PSD_V4.0]
Table 10 – Functional Families of Extended Components
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6 SECURITY REQUIREMENTS
Section 6 provides security functional and assurance requirements that must be
satisfied by a compliant TOE.
6.1 CONVENTIONS
The CC permits four types of operations to be performed on functional
requirements: selection, assignment, refinement, and iteration. This is defined
as:
• Assignment: Indicated by surrounding brackets and underline, e.g.,
[assigned item].
• Selection: Indicated by surrounding brackets and italics, e.g., [selected
item].
• Refinement: Refined components are identified by using [bold
surrounded by brackets] for additional information, or [strikeout
surrounded by brackets] for deleted text.
• Iteration: Iteration operations for iterations within the Protection Profile
and associated modules are identified with a slash (‘/’) and an identifier
(e.g. “/KM”). Where multiple iterations of the SFR are required within the
ST, a number is appended to the SFR identifier (e.g.
“FDP_CDS_EXT.1(1)”).
Extended SFRs are identified by the inclusion of “EXT” in the SFR name.
The CC operations already performed in the PP and PP modules are reproduced
in plain text and not denoted in this ST. The requirements have been copied
from the PP and PP modules and any remaining operations have been completed
herein. Refer to the PP and PP modules to identify those operations.
6.2 SECURITY FUNCTIONAL REQUIREMENTS
The security functional requirements for this ST consist of the following
components.
Class Identifier Name Source
User Data
Protection
(FDP)
FDP_APC_EXT.1/KM Active PSD Connections [MOD_KM_V1.0]
FDP_FIL_EXT.1/KM Device Filtering
(Keyboard/Mouse)
[MOD_KM_V1.0]3
3
There is no modification to this SFR in the [MOD_KM_V1.0]. However, there are
additions to the Peripheral Device Connections associated with this SFR and additional
evaluation activities.
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Class Identifier Name Source
FDP_PDC_EXT.1 Peripheral Device
Connection
[PP_PSD_V4.0]
[MOD_KM_V1.0]
FDP_PDC_EXT.2/KM Authorized Devices
(Keyboard/Mouse)
[MOD_KM_V1.0]
FDP_PDC_EXT.3/KM Authorized Connection
Protocols
(Keyboard/Mouse)
[MOD_KM_V1.0]
FDP_RDR_EXT.1 Re-Enumeration Device
Rejection
[MOD_KM_V1.0]
FDP_RIP_EXT.1 Residual Information
Protection
[PP_PSD_V4.0]
FDP_RIP.1/KM Residual Information
Protection (Keyboard
Data)
[MOD_KM_V1.0]
FDP_SWI_EXT.1 PSD Switching [PP_PSD_V4.0]
FDP_UDF_EXT.1/KM Unidirectional Data Flow
(Keyboard/Mouse)
[MOD_KM_V1.0]
Protection
of the TSF
(FPT)
FPT_FLS_EXT.1 Failure with
Preservation of Secure
State
[PP_PSD_V4.0]
FPT_NTA_EXT.1 No Access to TOE [PP_PSD_V4.0]
FPT_PHP.1 Passive Detection of
Physical Attack
[PP_PSD_V4.0]
FPT_TST.1 TSF testing [PP_PSD_V4.0]
FPT_TST_EXT.1 TSF Testing [PP_PSD_V4.0]
Table 11 – Summary of Security Functional Requirements
User Data Protection (FDP)
6.2.1.1 FDP_APC_EXT.1/KM Active PSD Connections
FDP_APC_EXT.1.1/KM The TSF shall route user data only to the interfaces selected by
the user.
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FDP_APC_EXT.1.2/KM The TSF shall ensure that no data or electrical signals flow
between connected computers whether the TOE is powered on
or powered off.
FDP_APC_EXT.1.3/KM The TSF shall ensure that no data transits the TOE when the
TOE is powered off.
FDP_APC_EXT.1.4/KM The TSF shall ensure that no data transits the TOE when the
TOE is in a failure state.
6.2.1.2 FDP_FIL_EXT.1/KM Device Filtering (Keyboard/Mouse)
FDP_FIL_EXT.1.1/KM The TSF shall have [fixed] device filtering for [keyboard, mouse]
interfaces.
FDP_FIL_EXT.1.2/KM The TSF shall consider all PSD KM blacklisted devices as
unauthorized devices for [keyboard, mouse] interfaces in
peripheral device connections.
FDP_FIL_EXT.1.3/KM The TSF shall consider all PSD KM whitelisted devices as
authorized devices for [keyboard, mouse] interfaces in
peripheral device connections only if they are not on the PSD KM
blacklist or otherwise unauthorized.
6.2.1.3 FDP_PDC_EXT.1 Peripheral Device Connection
FDP_PDC_EXT.1.1 The TSF shall reject connections with unauthorized devices upon
TOE power up and upon connection of a peripheral device to a
powered‐on TOE.
FDP_ PDC_EXT.1.2 The TSF shall reject connections with devices presenting
unauthorized interface protocols upon TOE power up and upon
connection of a peripheral device to a powered‐on TOE.
FDP_ PDC_EXT.1.3 The TOE shall have no external interfaces other than those claimed
by the TSF.
FDP_ PDC_EXT.1.4 The TOE shall not have wireless interfaces.
FDP_ PDC_EXT.1.5 The TOE shall provide a visual or auditory indication to the User
when a peripheral is rejected.
6.2.1.4 FDP_PDC_EXT.2/KM Authorized Devices
(Keyboard/Mouse)
FDP_PDC_EXT.2.1/KM The TSF shall allow connections with authorized devices and
functions as defined in Appendix E [of [MOD_KM_V1.0]] and
[
• no other devices
] upon TOE power up and upon connection of a peripheral
device to a powered-on TOE.
FDP_ PDC_EXT.2.2/KM The TSF shall allow connections with authorized devices
presenting authorized interface protocols as defined in
Appendix E [of [MOD_KM_V1.0]] and [
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• no other devices
] upon TOE power up and upon connection of a peripheral
device to a powered-on TOE.
6.2.1.5 FDP_PDC_EXT.3/KM Authorized Connection Protocols
(Keyboard/Mouse)
FDP_PDC_EXT.3.1/KM The TSF shall have interfaces for the [USB (keyboard), USB
(mouse)] protocols.
FDP_PDC_EXT.3.2/KM The TSF shall apply the following rules to the supported
protocols: the TSF shall emulate any keyboard or mouse device
functions from the TOE to the connected computer.
6.2.1.6 FDP_RDR_EXT.1 Re-Enumeration Device Rejection
FDP_RDR_EXT.1.1 The TSF shall reject any device that attempts to enumerate again as
a different unauthorized device.
6.2.1.7 FDP_RIP_EXT.1 Residual Information Protection
FDP_RIP_EXT.1.1 The TSF shall ensure that no user data is written to TOE non‐volatile
memory or storage.
6.2.1.8 FDP_RIP.1/KM Residual Information Protection
(Keyboard Data)
FDP_RIP.1.1/KM The TSF shall ensure that any keyboard data in volatile memory is
purged upon switching computers.
6.2.1.9 FDP_SWI_EXT.3 Tied Switching
FDP_SWI_EXT.3.1 The TSF shall ensure that connected keyboard and mouse peripheral
devices are always switched together to the same connected
computer.
6.2.1.10 FDP_SWI_EXT.1 PSD Switching
FDP_SWI_EXT.1.1 The TSF shall ensure that [the TOE supports only one connected
computer, switching can be initiated only through express user
action].
6.2.1.11 FDP_UDF_EXT.1/KM Unidirectional Data Flow
(Keyboard/Mouse)
FDP_UDF_EXT.1.1/KM The TSF shall ensure [keyboard, mouse] data transits the TOE
unidirectionally from the TOE [keyboard, mouse] peripheral
interface(s) to the TOE [keyboard, mouse] interface.
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Protection of the TSF (FPT)
6.2.2.1 FPT_FLS_EXT.1 Failure with Preservation of Secure
State
FPT_FLS_EXT.1.1 The TSF shall preserve a secure state when the following types
of failures occur: failure of the power‐on self‐test and [no other
failures].
6.2.2.2 FPT_NTA_EXT.1 No Access to TOE
FPT_NTA_EXT.1.1 TOE firmware, software, and memory shall not be accessible via the
TOE’s external ports, with the following exceptions: [no other
exceptions].
6.2.2.3 FPT_PHP.1 Passive Detection of Physical Attack
FPT_PHP.1.1 The TSF shall provide unambiguous detection of physical tampering
that might compromise the TSF.
FPT_PHP.1.2 The TSF shall provide the capability to determine whether physical
tampering with the TSF's devices or TSF's elements has occurred.
6.2.2.4 FPT_TST.1 TSF Testing
FPT_TST.1.1 The TSF shall run a suite of self tests during initial start-up and at the
conditions [no other conditions] to demonstrate the correct operation of
user control functions and [no other functions].
FPT_TST.1.2 The TSF shall provide authorized users with the capability to verify the
integrity of [TSF data].
FPT_TST.1.3 The TSF shall provide authorized users with the capability to verify the
integrity of [TSF].
6.2.2.5 FPT_TST_EXT.1 TSF Testing
FPT_TST_EXT.1.1 The TSF shall respond to a self‐test failure by providing users with a
[visual, auditory] indication of failure and by shutdown of normal
TSF functions.
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6.3 SECURITY ASSURANCE REQUIREMENTS
The assurance requirements are summarized in Table 12.
Assurance Class
Assurance Components
Identifier Name
Development (ADV) ADV_FSP.1 Basic Functional Specification
Guidance Documents
(AGD)
AGD_OPE.1 Operational user guidance
AGD_PRE.1 Preparative procedures
Life-Cycle Support
(ALC)
ALC_CMC.1 Labeling of the TOE
ALC_CMS.1 TOE CM Coverage
Security Target
Evaluation (ASE)
ASE_CCL.1 Conformance claims
ASE_ECD.1 Extended Components Definition
ASE_INT.1 ST Introduction
ASE_OBJ.2 Security Objectives
ASE_REQ.2 Derived Security Requirements
ASE_SPD.1 Security Problem Definition
ASE_TSS.1 TOE Summary Specification
Tests (ATE)
ATE_IND.1
Independent Testing -
Conformance
Vulnerability
Assessment (AVA)
AVA_VAN.1 Vulnerability Survey
Table 12 – Security Assurance Requirements
6.4 SECURITY REQUIREMENTS RATIONALE
Security Functional Requirements Rationale
Table 7 provides a mapping between the SFRs and Security Objectives.
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Dependency Rationale
Table 13 identifies the Security Functional Requirements and their associated
dependencies. It also indicates whether the ST explicitly addresses each
dependency.
SFR Dependencies Rationale Statement
FDP_APC_EXT.1/KM None N/A
FDP_FIL_EXT.1/KM FDP_PDC_EXT.1 Included
FDP_PDC_EXT.1 None N/A
FDP_PDC_EXT.2/KM FDP_PDC_EXT.1 Included
FDP_PDC_EXT.3/KM FDP_PDC_EXT.1 Included
FDP_RDR_EXT.1 FDP_PDC_EXT.1 Included
FDP_RIP_EXT.1 None N/A
FDP_RIP.1/KM None N/A
FDP_SWI_EXT.1 None N/A
FDP_UDF_EXT.1/KM FDP_APC_EXT.1 Included
FPT_FLS_EXT.1 FPT_TST.1
FPT_PHP.3
Included
N/A (only required if anti‐tamper is
selected in FPT_FLS_EXT.1.1).
FPT_NTA_EXT.1 None N/A
FPT_PHP.1 None N/A
FPT_TST.1 None N/A
FPT_TST_EXT.1 FPT_TST.1 Included
Table 13 – Functional Requirement Dependencies
Security Assurance Requirements Rationale
The TOE assurance requirements for this ST consist of the requirements
indicated in the [PP_PSD_V4.0].
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7 TOE SUMMARY SPECIFICATION
This section provides a description of the security functions and assurance
measures of the TOE that meet the TOE security requirements.
7.1 USER DATA PROTECTION
System Controller
Each device includes a System Controller which is responsible for device
management, system control security functions, and device monitoring.
The System Controller includes a microcontroller with internal non-volatile, Read
Only Memory (ROM). The controller function manages the TOE functionality
through a pre-programmed state machine loaded on the ROM as read-only
firmware during product manufacturing.
The TOE supports only one connected computer.
TOE Security Functional Requirements addressed: FDP_SWI_EXT.1.
7.1.1.1 Active PSD Connections
The TOE ensures that data flows only one-way between the peripherals and the
connected computer. No data transits the TOE when the TOE is powered off, or
when the TOE is in a failure state. A failure state occurs when the TOE fails a
self-test when powering on.
TOE Security Functional Requirements addressed: FDP_APC_EXT.1/KM.
7.1.1.2 Connected Computer Interfaces
The connected computers are attached to the TOE as follows:
• The TOE connects to the keyboard and mouse port using a USB A to USB
B cable. The USB A end attaches to the computer, and the USB B end
attaches to the TOE
TOE Security Functional Requirements addressed: FDP_PDC_EXT.1.
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7.1.1.3 Residual Information Protection
The Letter of Volatility is included as Annex A.
TOE Security Functional Requirements addressed: FDP_RIP_EXT.1.
Keyboard and Mouse Functionality
7.1.2.1 Keyboard and Mouse Enumeration
The TOE determines whether or not a peripheral device that has been plugged
into the keyboard and mouse peripheral ports is allowed to operate with the
TOE. The TOE uses optical data diodes to enforce a unidirectional data flow from
the user peripherals to the coupled host and uses isolated device emulators to
prevent data leakage through the peripheral switching circuitry.
The Static Random Access Memory (SRAM) in the host and device emulator
circuitry stores USB Host stack parameters and up to the last 4 key codes. User
data may be briefly retained; however, there are no data buffers. Data is erased
during power off of the device.
The TOE supports USB Type A HIDs on keyboard and mouse ports. The USB
bidirectional communication protocol is converted into a unidirectional
proprietary protocol, and is then converted back into the USB bidirectional
protocol to communicate with the coupled computer host.
A USB keyboard is connected to the TOE keyboard host emulator through the
console keyboard port. The keyboard host emulator is a microcontroller which
enumerates the connected keyboard and verifies that it is a permitted device
type. Once the keyboard has been verified, the USB keyboard sends scan codes,
which are generated when the user types. These scan codes are converted by
the keyboard host emulator into a proprietary protocol data stream that is
combined with the data stream from the mouse host emulator.
Similarly, the USB mouse is connected to the TOE mouse host emulator through
the USB mouse port. The mouse host emulator is a microcontroller which
enumerates the connected mouse and verifies that it is a permitted device type.
Once the mouse device has been verified, it sends serial data generated by
mouse movement and button use. The mouse serial data is converted by the
mouse host emulator into a proprietary protocol data stream that is combined
with the data stream from the keyboard host emulator.
TOE Security Functional Requirements addressed: FDP_PDC_EXT.3/KM,
FDP_UDF_EXT.1/KM.
7.1.2.2 Keyboard and Mouse Data Stream
The combined mouse and keyboard data stream is passed through an optical
data diode and routed to the host device emulator. The optical data diode is an
opto-coupler designed to physically prevent reverse data flow.
Device emulators are USB enabled microcontrollers that are programmed to
emulate a standard USB keyboard and mouse composite device. The combined
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data stream is converted back to bidirectional data before reaching the host
computer.
Since the keyboard and mouse function are emulated by the TOE, the connected
computer is not able to send data to the keyboard that would allow it to indicate
that Caps Lock, Num Lock or Scroll Lock are set. These are indicated on the TOE
front panel, on the right hand side.
7.1.2.3 Keyboard and Mouse Compatible Device Types
The TOE employs fixed device filtering and accepts only USB HID devices at the
keyboard and mouse peripheral ports. Only USB Type A connections are
permitted. The TOE does not support a wireless connection to a mouse,
keyboard or USB hub.
TOE Security Functional Requirements addressed: FDP_PDC_EXT.1,
FDP_PDC_EXT.2/KM, FDP_FIL_EXT.1/KM.
7.1.2.4 Re-Enumeration Device Rejection
If a connected device attempts to re-enumerate as a different USB device type,
it will be rejected by the TOE. The TOE will reject devices which are not allowed
at any time during operation and start-up. This is indicated by an LED on the
TOE next to the Keyboard and mouse ports. This LED shows a solid green light
for an accepted device, flickering green light during enumeration, and no light
for a rejected device.
TOE Security Functional Requirements addressed: FDP_RDR_EXT.1.
7.2 PROTECTION OF THE TSF
No Access to TOE
The connected computer does not have access to TOE firmware or memory.
The TOE microcontroller runs from internal protected flash memory. Firmware
cannot be updated from an external source. Firmware cannot be read or
rewritten through the use of Joint Test Action Group (JTAG) tools. Firmware is
executed on Static Random Access Memory (SRAM) with the appropriate
protections to prevent external access and tampering of code or stacks.
TOE Security Functional Requirements addressed: FPT_NTA_EXT.1.
Anti-tampering Functionality
The TOE provides passive anti-tampering functionality.
7.2.2.1 Passive Detection of Physical Tampering
The TOE enclosure was designed specifically to prevent physical tampering and
features fitted molded plastic parts.
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Additionally, each device is fitted with one or more holographic Tampering
Evident Labels placed at critical locations on the TOE enclosure. If the label is
removed, the word ‘VOID’ appears on both the label and the product surface.
TOE Security Functional Requirements addressed: FPT_PHP.1.
TSF Testing
The TOE performs a self-test at initial start-up to verify the integrity of the
microcontroller firmware.
If the self-test fails, the LEDs on the front panel blink to indicate the failure. The
TOE remains in a disabled state until the self-test is rerun and passes.
TOE Security Functional Requirements addressed: FPT_FLS_EXT.1(1),
FPT_TST.1, FPT_TST_EXT.1.
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8 TERMINOLOGY AND ACRONYMS
8.1 TERMINOLOGY
The following terminology is used in this ST:
Term Description
KM KM refers to the requirements for Keyboard/Mouse Devices.
Table 14 – Terminology
8.2 ACRONYMS
The following acronyms are used in this ST:
Acronym Definition
CC Common Criteria
DE Device Emulator
EEPROM Electrically Erasable Programmable Read-Only Memory
HE Host Emulator
HID Human Interface Device
HSL High Sec Labs
IT Information Technology
JTAG Joint Test Action Group
KM Keyboard, Mouse
LED Light Emitting Diode
NIAP National Information Assurance Partnership
OTP One Time Programming
PP Protection Profile
PSD Peripheral Sharing Device
ROM Read Only Memory
SFR Security Functional Requirement
SRAM Static Random Access Memory
ST Security Target
TOE Target of Evaluation
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Acronym Definition
TSF TOE Security Functionality
USB Universal Serial Bus
Table 15 – Acronyms
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9 REFERENCES
Identifier Title
[CC] Common Criteria for Information Technology Security
Evaluation –
• Part 1: Introduction and General Model, CCMB‐2017‐
04‐001, Version 3.1 Revision 5, April 2017
• Part 2: Security Functional Components, CCMB‐2017‐
04‐002, Version 3.1 Revision 5, April 2017
• 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
[PP_PSD_V4.0] Protection Profile for Peripheral Sharing Device, Version: 4.0,
2019‐07‐19
[MOD_KM_V1.0] PP‐Module for Keyboard/Mouse Devices, Version 1.0, 2019-
07-19
[CFG_PSD‐
KM_V1.0]
PP‐Configuration for Peripheral Sharing Device and
Keyboard/Mouse Devices, 19 July 2019
Table 16 – References
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ANNEX A – LETTER OF VOLATILITY
The table below provides volatility information and memory types for the High Sec Labs Peripheral Sharing Devices
with keyboard and mouse. User data is not retained in any TOE device when the power is turned off.
Product
Model
No. in
each
product
Function,
Manufacturer
and Part
Number
Power Source
(if not the TOE)
Storage Type Size Volatility Contains User
Data
FH10N-4 1 System Controller,
Host emulator:
NXP
MIMXRT1052DVJ6B
Connected
computer
Embedded SRAM1
512KB Volatile May contain user data
Embedded Flash2
256KB Non-Volatile No user data
Embedded
EEPROM3
4KB Non-Volatile No user data
OTP Memory 512bytes Non-Volatile No user data
1 Boot flash for USB
Controller
System Controller,
Host Emulator
External Flash 2MB Volatile No user data
1 Device emulator:
ST Microelectronics
STM32F070C6T6
Connected
computer
Embedded SRAM1
6KB Volatile May contain user data
Embedded Flash2
32KB Non-Volatile No user data
Embedded
EEPROM3
4KB Non-Volatile No user data
Notes:
1
SRAM stores USB Host stack parameters and up to the last 4 key-codes. Data is erased during power off of the device. Device
emulators receive power from the connected computer and therefore devices are powered on as long as the associated
computer is powered on and connected.
2
Flash storage is used to store firmware code. It contains no user data. Flash storage is permanently locked by fuses after
initial programming to prevent rewriting. It is an integral part of the microcontroller together with SRAM and EEPROM.
3
EEPROM is used to store operational parameters. They contain no user data. These devices receive power from the computer
connected to the TOE, and therefore are powered on as long as the associated computer is powered on and connected.