High Sec Labs
SK41D-4TR KVM
Firmware Version 44404-E7E7
Security Target
Doc No: 2149-001-D102A5
Version: 1.7
14 September 2021
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
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page i of ii
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 ....................................................................... 5
Evaluated Configuration ..................................................................5
Ports and Protocols.........................................................................6
Physical Scope ...............................................................................8
Logical Scope.................................................................................9
2 CONFORMANCE CLAIMS.............................................................11
2.1 COMMON CRITERIA CONFORMANCE CLAIM .................................... 11
2.2 PP-CONFIGURATION CONFORMANCE CLAIM ................................... 11
2.3 TECHNICAL DECISIONS............................................................... 12
2.4 PACKAGE CLAIM......................................................................... 12
2.5 CONFORMANCE RATIONALE ......................................................... 12
3 SECURITY PROBLEM DEFINITION..............................................13
3.1 THREATS .................................................................................. 13
3.2 ORGANIZATIONAL SECURITY POLICIES ......................................... 14
3.3 ASSUMPTIONS........................................................................... 14
4 SECURITY OBJECTIVES..............................................................16
4.1 SECURITY OBJECTIVES FOR THE TOE ............................................ 16
4.2 SECURITY OBJECTIVES FOR THE OPERATIONAL ENVIRONMENT......... 21
4.3 SECURITY OBJECTIVES RATIONALE............................................... 22
5 EXTENDED COMPONENTS DEFINITION......................................27
5.1 CLASS FDP: USER DATA PROTECTION ........................................... 27
FDP_APC_EXT Active PSD Connections............................................27
FDP_CDS_EXT Connected Displays Supported..................................28
FDP_FIL_EXT Device Filtering ........................................................29
FDP_PDC_EXT Peripheral Device Connection....................................30
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page ii of iii
FDP_RDR_EXT Re-Enumeration Device Rejection .............................32
FDP_RIP_EXT Residual Information Protection .................................32
FDP_SPR_EXT Sub-Protocol Rules ..................................................33
FDP_SWI_EXT PSD Switching ........................................................34
FDP_UDF_EXT Unidirectional Data Flow...........................................35
5.2 CLASS FPT: PROTECTION OF THE TSF ........................................... 36
FPT_FLS_EXT Failure with Preservation of Secure State ....................36
FPT_NTA_EXT No Access to TOE.....................................................36
FPT_TST_EXT TSF Testing .............................................................37
5.3 CLASS FTA: TOE ACCESS ............................................................ 38
FTA_CIN_EXT Continuous Indications .............................................38
6 SECURITY REQUIREMENTS ........................................................40
6.1 CONVENTIONS........................................................................... 40
6.2 SECURITY FUNCTIONAL REQUIREMENTS........................................ 40
Security Audit (FAU).....................................................................42
User Data Protection (FDP)............................................................42
Identification and Authentication....................................................46
Security Management (FMT) ..........................................................46
Protection of the TSF (FPT)............................................................47
TOE Access (FTA).........................................................................48
6.3 SECURITY ASSURANCE REQUIREMENTS......................................... 48
6.4 SECURITY REQUIREMENTS RATIONALE.......................................... 50
Security Functional Requirements Rationale.....................................50
Dependency Rationale ..................................................................50
Security Assurance Requirements Rationale.....................................51
7 TOE SUMMARY SPECIFICATION.................................................52
7.1 SECURITY AUDIT........................................................................ 52
7.2 USER DATA PROTECTION ............................................................ 52
System Controller ........................................................................52
Keyboard and Mouse Functionality..................................................54
Video Switching Functionality.........................................................56
7.3 IDENTIFICATION AND AUTHENTICATION AND SECURITY MANAGEMENT
60
7.4 PROTECTION OF THE TSF ............................................................ 61
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page iii of iv
No Access to TOE .........................................................................61
Anti-tampering Functionality..........................................................62
Reliable Timestamps.....................................................................62
TSF Testing .................................................................................63
7.5 TOE ACCESS.............................................................................. 63
8 TERMINOLOGY AND ACRONYMS ................................................64
8.1 TERMINOLOGY........................................................................... 64
8.2 ACRONYMS................................................................................ 64
9 REFERENCES..............................................................................66
ANNEX A – LETTER OF VOLATILITY .................................................... A-1
LIST OF TABLES
Table 1 – Non-TOE Hardware and Software................................................. 4
Table 2 – KVM Switch Interfaces and Protocols ............................................ 7
Table 3 – Remote Control Interfaces and Protocols....................................... 8
Table 4 – TOE Devices ............................................................................. 8
Table 5 – Logical Scope of the TOE .......................................................... 10
Table 6 – Applicable Technical Decisions ................................................... 12
Table 7 – Threats.................................................................................. 14
Table 8 – Assumptions........................................................................... 15
Table 9 – Security Objectives for the TOE ................................................. 20
Table 10 – Security Objectives for the Operational Environment ................... 21
Table 11 – Security Objectives Rationale .................................................. 26
Table 12 – Functional Families of Extended Components ............................. 27
Table 13 – Summary of Security Functional Requirements........................... 42
Table 14 – Security Assurance Requirements............................................. 49
Table 15 – Functional Requirement Dependencies ...................................... 51
Table 16 – Terminology ......................................................................... 64
Table 17 – Acronyms............................................................................. 65
Table 18 – References ........................................................................... 66
Table 19 – Letter of Volatility................................................................. A-1
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page iv of iv
LIST OF FIGURES
Figure 1 – KVM Switch Evaluated Configuration ........................................... 5
Figure 2 – KVM Switch Front and Rear View ................................................ 6
Figure 3 – Remote Control........................................................................ 7
Figure 4 – Simplified Switching Diagram................................................... 55
Figure 5 – Display EDID Read Function..................................................... 57
Figure 6 – Display EDID Write Function .................................................... 58
Figure 7 – Display Normal Mode .............................................................. 59
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 1 of 66
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 Modules.
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 SK41D-4TR KVM Firmware Version
44404-E7E7 Security Target
ST Version: 1.7
ST Date: 14 September 2021
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 2 of 66
1.3 TOE REFERENCE
TOE Identification: High Sec Labs SK41D-4TR KVM Firmware Version
44404-E7E7
TOE Developer: High Sec Labs Ltd.
TOE Type: The TOE is a Peripheral Sharing Device as defined in
the Protection Profile for Peripheral Sharing Device,
Version 4.0 [PP_PSD_V4.0]
1.4 TOE OVERVIEW
The High Sec Labs (HSL) SK41D-4TR Keyboard, Video, Mouse (KVM) switch
allows users to share keyboard, video, and mouse peripherals between a
number of connected computers. Security features ensure isolation between
computers and peripherals to prevent data leakage between connected systems.
The following security features are provided by the HSL Peripheral Sharing
Devices:
• Security Audit
o Audit entries are generated for security related events.
• User Data Protection
o The TOE provides secure switching capabilities for keyboard, video
and mouse. The TOE ensures that only authorized peripheral
devices may be used.
• Video Security
o Computer video input interfaces are isolated through
the use of separate electronic components, power and
ground domains.
o The display is isolated by dedicated, read-only,
Extended Display Identification Data (EDID) emulation
for each computer.
o Access to the monitor’s EDID is blocked.
o Access to the Monitor Control Command Set (MCCS
commands) is blocked.
o Digital Visual Interface (DVI)-D video is supported.
• Keyboard and Mouse Security
o The keyboard and mouse are isolated by dedicated,
Universal Serial Bus (USB) device emulation for each
computer.
o One-way, peripheral-to-computer data flow is enforced
through unidirectional optical data diodes.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 3 of 66
o Communication from computer-to-keyboard/mouse is
blocked.
o Non-HID (Human Interface Device) data transactions
are blocked.
• Identification and Authentication
o Administrators must be identified and authenticated prior to
accessing administrative functions.
• Security Management
o The TOE provides management capabilities in support of the
‘Restore to factory default’ function. The Administrator role restricts
this functionality to authorized administrators.
• Protection of the TSF1
o The TOE ensures a secure state in the case of failure, provides only
restricted access, and performs self-testing.
o The TOE provides both passive detection of physical attack and
resistance to physical attack:
• Any attempt to open the product enclosure will activate an anti-
tampering system, making the product inoperable and
indicating tampering via blinking Light Emitting Diodes (LEDs).
• Special holographic tampering evident labels on the product’s
enclosure provide a clear visual indication if the product has
been opened or compromised.
o Reliable timestamps are provided for audit records.
• TOE Access
o The TOE provides a continuous indication of which computer is
currently selected.
The High Sec Labs SK41D-4TR KVM uses multiple isolated microcontrollers (one
microcontroller per connected computer) to emulate connected peripherals in
order to prevent an unauthorized data flow through bit-by-bit signaling.
The TOE is a combined software and hardware TOE.
TOE Environment
The following components are required for operation of the TOE in the evaluated
configuration.
1
TOE Security Functionality
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 4 of 66
Component Description
Connected Computers 4 General purpose computers
Keyboard General purpose USB keyboard
Mouse General purpose USB mouse
User display Standard DVI-D computer display
HSL KVM Cables Ruggedized 32 pin console cable. The console cable has a
round 32 pin connector on the KVM side. On the
peripheral side, there is a DVI-D video connector, two
USB 2.0 connectors for the keyboard and mouse and a
port for connecting the WR40-4R remote control.
Ruggedized 32 pin PC cables. The PC cables have a single
round 32 pin connector on the KVM side. On the PC side,
there is a DVI-D video connector and two USB 2.0
connectors for the keyboard and mouse.
Power Supply 28 Volt Direct Current (VDC) Power Supply. A Dr.Meter
HY3005F-3 Programmable power supply is used in the
evaluated configuration.
Table 1 – Non-TOE Hardware and Software
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 5 of 66
1.5 TOE DESCRIPTION
Evaluated Configuration
Figure 1 – KVM Switch Evaluated Configuration
Figure 1 shows a basic evaluated configuration. The TOE is connected to four
computers. The video input and output format is DVI-D, and a single display is
connected to the KVM. The TOE uses ruggedized 32 pin connectors (MIL Spec
MIL-DTL-38999) that support both DVI-D and USB 2.0 protocols. The KVM is
used with a wired remote control.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 6 of 66
Ports and Protocols
Figure 2 – KVM Switch Front and Rear View
Figure 2 shows the front and rear view of the KVM switch. The interfaces are
described in Table 2.
Interface Protocol or Usage
A Channel LED Visual indication of the selected channel
B Channel selection
button
Manual pushbutton interface
C USB (Keyboard or
Mouse) LED
Visual indication of the HID status:
• Off indicates no device detected
• Red indicates device rejected
• Green indicates device approved
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 7 of 66
Interface Protocol or Usage
D USB (Keyboard or
Mouse) LED
Visual indication of the HID status:
• Off indicates no device detected
• Red indicates device rejected
• Green indicates device approved
E EDID Capture LED Visual indication of the EDID status:
• Off indicates no EDID
• Green flicker indicates EDID read in progress
• Green indicates EDID received
F Console and RCU
Cable Port
32 pin connector supporting DVI-D, a serial
connection (RS-232 protocol) and 2 USB 2.0
connections. This port is used with the provided
cable.
G PC Cable Ports 32 pin connector supporting DVI-D and two USB
2.0 connections. These ports are used with the
provided cables.
H Power input The input to the device is 28 VDC.
Table 2 – KVM Switch Interfaces and Protocols
Figure 3 – Remote Control
Figure 3 shows the TOE remote control. The interfaces are described in Table 3.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 8 of 66
Interface Protocol or Usage
I Channel selection
button
Manual pushbutton interface
Pressing the button causes the device to switch to
the next sequential channel. The channel is set by
pressing the remote control button until the desired
channel is selected.
J Channel LEDs Visual indication of the selected channel
There are four LEDs in the first row. The LED is
illuminated when the associated channel is
selected.
K USB (Keyboard or
Mouse) LED
Visual indication of the HID status:
• Off indicates no device detected
• Flicker indicates device rejected
• On indicates device approved
L USB (Keyboard or
Mouse) LED
Visual indication of the HID status:
• Off indicates no device detected
• Flicker indicates device rejected
• On indicates device approved
M EDID Capture LED Visual indication of the EDID status:
• Off indicates no EDID
• Flicker indicates EDID read in progress
• On indicates EDID received
N RCU Connector This interface supports an RS-232 protocol serial
connection. The interface is a round 32 pin
ruggedized connector.
Table 3 – Remote Control Interfaces and Protocols
Physical Scope
Table 4 describes the TOE device.
Family Description Part Number Model
Ruggedized KVM Switch CGA21853 SK41D-4TR
Remote Control CGA22528 WR40-4R
Table 4 – TOE Devices
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 9 of 66
1.5.3.1 TOE Delivery
The TOE, together with its corresponding cables are delivered to the customer
via trusted carrier, such as Fed-Ex, that provide a tracking service for all
shipments.
1.5.3.2 TOE Guidance
The TOE includes the following guidance documentation, which may be
downloaded from the High Sec Labs website (www.highseclabs.com) in .pdf
format:
• HSL Quick Installation Guide 4 Ports Secure Ruggedized DVI-D KVM
Switch, HDC23220 Rev 1.2
• HSL Administrator Guide, HDC19968, Rev. C
The following guidance is available upon request by emailing
support@highseclabs.com:
• High Sec Labs SK41D-4TR KVM Firmware Version 44404-E7E7 Common
Criteria Guidance Supplement, Version 0.5
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 5 summarizes the logical
scope of the TOE.
Functional Classes Description
Security Audit Audit entries are generated for security related events.
User Data Protection The TOE provides secure switching capabilities for
keyboard, video and mouse. The TOE ensures that only
authorized peripheral devices may be used.
Identification and
Authentication
Administrators must be identified and authenticated prior
to accessing administrative functions.
Security Management The TOE provides management capabilities in support of
the ‘Restore to factory default’ function. The Administrator
role restricts this functionality to authorized administrators.
Protection of the TSF The TOE ensures a secure state in the case of failure,
provides only restricted access, and performs self-testing.
The TOE provides both passive detection of physical attack
and resistance to physical attack. Reliable time stamps are
provided for audit records.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 10 of 66
Functional Classes Description
TOE Access The TOE provides a continuous indication of which
computer is currently selected.
Table 5 – Logical Scope of the TOE
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 11 of 66
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 PP-CONFIGURATION CONFORMANCE CLAIM
PP-Configuration for Peripheral Sharing Device, Keyboard/Mouse Devices, and
Video/Display Devices, 19 July 2019 [CFG_PSD-KM-VI_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]
• PP-Module: PP-Module for Video/Display Devices, Version 1.0
[MOD_VI_V1.0]
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 12 of 66
2.3 TECHNICAL DECISIONS
The Technical Decisions in Table 6 apply to the PP and the modules and have
been accounted for in the ST and in the evaluation.
Technical Decision PP or Module
TD0506 [MOD_VI_V1.0]
TD0507 [MOD_KM_V1.0]
TD0514 [MOD_VI_V1.0]
TD0518 [PP_PSD_V4.0]
TD0539 [MOD_VI_V1.0]
TD0583 [PP_PSD_V4.0]
TD0584 [MOD_VI_V1.0]
TD0586 [MOD_VI_V1.0]
TD0593 [MOD_KM_V1.0], [MOD_VI_V1.0]
Table 6 – Applicable Technical Decisions
2.4 PACKAGE CLAIM
This Security Target does not claim conformance with any package.
2.5 CONFORMANCE RATIONALE
The TOE is inherently consistent with the Compliant Targets of Evaluation
described in the [PP_PSD_V4.0] and in the PP modules listed in Section 2.2, and
with the PP‐Configuration for Peripheral Sharing Device, Keyboard/Mouse
Devices, and Video/Display Devices [CFG_PSD‐KM-VI_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 modules listed in Section 2.2.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 13 of 66
3 SECURITY PROBLEM DEFINITION
3.1 THREATS
Table 7 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
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 14 of 66
Threat Description
T.FAILED Detectable failure of a PSD may cause an
unauthorized information flow or weakening of PSD
security functions.
Table 7 – 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 8.
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.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 15 of 66
Assumptions Description
A.NO_SPECIAL_ANALOG
_CAPABILITIES
The computers connected to the TOE are not equipped
with special analog data collection cards or peripherals
such as analog to digital interface, high performance
audio interface, digital signal processing function, or
analog video capture function.
Table 8 – Assumptions
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 16 of 66
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_VI FDP_APC_EXT.1/VI, 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
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_VI FDP_APC_EXT.1/VI, 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
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 17 of 66
Security Objective Description
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_VI FDP_APC_EXT.1/VI, 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
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:
PP_PSD FDP_RIP_EXT.1
MOD_KM FDP_RIP.1/KM, FDP_RIP_EXT.2
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, FDP_SWI_EXT.2
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
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 18 of 66
Security Objective Description
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 FAU_GEN.1, FDP_SWI_EXT.1, FDP_SWI_EXT.2,
FIA_UAU.2, FIA_UID.2, FMT_MOF.1,
FMT_SMF.1, FMT_SMR.1, FPT_STM.1,
FTA_CIN_EXT.1
MOD_VI FDP_CDS_EXT.1, FTA_CIN_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:
MOD_VI FDP_APC_EXT.1/VI, 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
O.REJECT
_UNAUTHORIZED
_PERIPHERAL
The PSD shall reject unauthorized peripheral device types and
protocols.
Addressed by:
PP_PSD FDP_PDC_EXT.1
MOD_VI FDP_PDC_EXT.2/VI, FDP_PDC_EXT.3/VI,
SPR_EXT.1/DVI-D
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,
FDP_PDC_EXT.3/KM
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 19 of 66
Security Objective Description
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,
FDP_SWI_EXT.3
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
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, FPT_PHP.3
O.SELF_TEST The PSD shall perform self‐tests following power up or
powered reset.
Addressed by:
PP_PSD FPT_TST.1
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 20 of 66
Security Objective Description
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.PROTECTED
_EDID
The TOE shall read the connected display Extended Display
Identification Data (EDID) once during the TOE power up or
reboot sequence and prevent any EDID channel write
transactions that connected computers initiate.
Addressed by:
MOD_VI FDP_PDC_EXT.2/VI, FDP_SPR_EXT.1/DVI-D
O.UNIDIRECTIONAL
_VIDEO
The TOE shall enforce unidirectional video data flow from the
connected computer video interface to the display interface
only.
Addressed by:
MOD_VI FDP_UDF_EXT.1/VI
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 9 – Security Objectives for the TOE
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 21 of 66
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.
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.
OE.NO_SPECIAL_ANALOG
_CAPABILITIES
The operational environment will not have special
analog data collection cards or peripherals such as
analog to digital interface, high performance audio
interface, or a component with digital signal
processing or analog video capture functions.
Table 10 – Security Objectives for the Operational Environment
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 22 of 66
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.
O.UNIDIRECTIONAL
_INPUT
The TOE’s enforcement of
unidirectional input for
keyboard/mouse data prevents
leakage of computer data through a
connected peripheral interface.
O.PROTECTED_EDID The TOE’s protection of the EDID
interface prevents its use as a vector
for unauthorized data leakage via this
channel.
O.UNIDIRECTIONAL
_VIDEO
The TOE’s enforcement of
unidirectional output for video data
protects against data leakage via
connected computers by ensuring
that no video data can be input to a
connected computer through this
interface.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 23 of 66
Threat or
Assumption
Security
Objective(s)
Rationale
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.
O.PROTECTED_EDID The TOE’s protection of the EDID
interface prevents its use as a vector
for bit‐by‐bit signal leakage via this
channel.
O.UNIDIRECTIONAL
_VIDEO
The TOE’s enforcement of
unidirectional output for video data
protects against signaling leakage via
connected computers by ensuring
that no video data can be input to a
connected computer through this
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.
O.PROTECTED_EDID The TOE’s protection of the EDID
interface prevents the leakage of
residual data by ensuring that no
such data can be written to EDID
memory.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 24 of 66
Threat or
Assumption
Security
Objective(s)
Rationale
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.
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.
O.UNIDIRECTIONAL
_VIDEO
The TOE’s limitation of supported
video protocol interfaces prevents the
connection of unauthorized devices.
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.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 25 of 66
Threat or
Assumption
Security
Objective(s)
Rationale
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
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
_DEVICES
OE.NO_WIRELESS
_DEVICES
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.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 26 of 66
Threat or
Assumption
Security
Objective(s)
Rationale
A.USER_ALLOWED
_ACCESS
OE.PHYSICAL If the TOE’s operational environment
provides physical access to connected
computers, then the assumption is
satisfied.
A.NO_SPECIAL
_ANALOG
_CAPABILITIES
OE.NO_SPECIAL
_ANALOG
_CAPABILITIES
If administrators in the TOE’s
operational environment take care to
ensure that computers with special
analog data collection interfaces are
not connected to the TOE, then the
assumption that such components
are not present is satisfied.
Table 11 – Security Objectives Rationale
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 27 of 66
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 modules for
keyboard/mouse devices [MOD_KM_V1.0] and display devices [MOD_VI_1.0]. It
is repeated here to ensure the completeness of this ST.
The families to which these components belong are identified in the following
table:
Functional Class Functional Families
User Data Protection (FDP) FDP_APC_EXT Active PSD Connections
FDP_CDS_EXT Connected Displays Supported
FDP_FIL_EXT Device Filtering
FDP_PDC_EXT Peripheral Device Connection
FDP_RDR_EXT Re-Enumeration Device Rejection
FDP_RIP_EXT Residual Information Protection
FDP_SPR_EXT Sub-Protocol Rules
FDP_SWI_EXT PSD Switching
FDP_UDF_EXT Unidirectional Data Flow
Protection of the TSF (FPT) FPT_FLS_EXT Failure with Preservation of Secure State
FPT_NTA_EXT No Access to TOE
FPT_TST_EXT TSF Testing
TOE Access (FTA) FTA_CIN_EXT Continuous Indications
Table 12 – Functional Families of Extended Components
5.1 CLASS FDP: USER DATA PROTECTION
FDP_APC_EXT Active PSD Connections
Family Behavior
Components in this family define the requirements for when an external
interface to the TOE is authorized to transmit data related to peripheral sharing.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 28 of 66
Component Leveling
FDP_APC_EXT.1 Active PSD Connections, restricts the flow of data through the
TSF.
Management: FDP_APC_EXT.1
No specific management functions are identified.
Audit: FDP_APC_EXT.1
There are no auditable events foreseen.
FDP_APC_EXT.1 Active PSD Connections
Hierarchical to: No other components.
Dependencies: No dependencies
FDP_APC_EXT.1.1 The TSF shall route user data only to or from the interfaces selected
by the user.
FDP_APC_EXT.1.2 The TSF shall ensure that no data flows between connected
computers whether the TOE is powered on or powered off.
FDP_APC_EXT.1.3 The TSF shall ensure that no data transits the TOE when the TOE is
powered off.
FDP_APC_EXT.1.4 The TSF shall ensure that no data transits the TOE when the TOE is
in a failure state.
FDP_CDS_EXT Connected Displays Supported
Family Behavior
Components in this family define requirements for the number of display
interfaces contained within the TOE.
Component Leveling
FDP_CDS_EXT.1, Connected Displays Supported, requires the TSF to define
whether it supports one connected display at a time or multiple connected
displays simultaneously.
FDP_APC_EXT Active PSD
Connections
1
FDP_CDS_EXT Connected
Displays Supported
1
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 29 of 66
Management: FDP_CDS_EXT.1
There are no specific management functions identified.
Audit: FDP_CDS_EXT.1
There are no auditable events foreseen.
FDP_CDS_EXT.1 Connected Displays Supported
Hierarchical to: No other components
Dependencies: No other components
FDP_CDS_EXT.1.1 The TSF shall support [selection: one connected display, multiple
connected displays] at a time.
FDP_FIL_EXT Device Filtering
Family Behavior
Components in this family define the requirements for device filtering.
Component Leveling
FDP_FIL_EXT.1 Device Filtering, requires the TSF to specify the method of
device filtering used for peripheral interfaces and defines requirements for
handling whitelists and blacklists.
Management: FDP_FIL_EXT.1
The following actions could be considered for the management functions in FMT:
• Ability to configure whitelist/blacklist members
Audit: FDP_FIL_EXT.1
The following actions should be auditable if FAU_GEN.1 Audit Data Generation is
included in the PP/ST:
• Configuration of whitelist/blacklist members
FDP_FIL_EXT.1 Device Filtering
Hierarchical to: No other components
Dependencies: FDP_PDC_EXT.1 Peripheral Device Connection
FDP_FIL_EXT.1.1 The TSF shall have [selection: configurable, fixed] device filtering for
[assignment: list of supported peripheral interface types] interfaces.
FDP_FIL_EXT.1.2 The TSF shall consider all [assignment: blacklist name] blacklisted
devices as unauthorized devices for [assignment: list of supported
peripheral interface types] interfaces in peripheral device
connections.
FDP_FIL_EXT Device
Filtering
1
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 30 of 66
FDP_FIL_EXT.1.3 The TSF shall consider all [assignment: whitelist name] whitelisted
devices as authorized devices for peripheral device connections only
if they are not on the [assignment: blacklist name] blacklist or
otherwise unauthorized.
FDP_PDC_EXT Peripheral Device Connection
Family Behavior
Components in this family define the requirements for peripheral device
connections.
This family is defined in the PSD PP. The PP‐Modules [MOD_KM_V1.0],
[MOD_VI_V1.0] augment the extended family by adding two additional
components, FDP_PDC_EXT.2 and FDP_PDC_EXT.3. The new components and
their impact on the extended family’s component leveling are shown below;
reference the PSD PP for all other definitions for this family.
Component Leveling
FDP_PDC_EXT.1 Peripheral Device Connection, requires the TSF to limit external
connections to only authorized devices.
FDP_PDC_EXT.2 Authorized Devices, defines the types of physical devices that
the TSF will permit to connect to it.
FDP_PDC_EXT.3, Authorized Connection Protocols, defines the protocols that the
TSF will authorize over its physical/logical interfaces, as well as any rules that
are applicable to these interfaces.
Management: FDP_PDC_EXT.1, FDP_PDC_EXT.2, FDP_PDC_EXT.3
No specific management functions are identified.
Audit: FDP_PDC_EXT.1
The following actions should be auditable if FAU_GEN.1 Audit Data Generation is
included in the PP/ST:
• Acceptance or rejection of a peripheral
FDP_PDC_EXT Peripheral
Device Connection
1
2
3
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 31 of 66
Audit: FDP_PDC_EXT.2, FDP_PDC_EXT.3
There are no specific auditable events foreseen.
FDP_PDC_EXT.1 Peripheral Device Connection
Hierarchical to: No other components.
Dependencies: No dependencies
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.
FDP_PDC_EXT.2 Authorized Devices
Hierarchical to: No other components.
Dependencies: FDP_PDC_EXT.1 Peripheral Device Connection
FDP_PDC_EXT.2.1 The TSF shall allow connections with authorized devices as defined
in [assignment: devices specified in the PP or PP‐Module in which
this SFR is defined] and [assignment: devices specified in another
PP or PP‐Module that shares a PP Configuration with the PP or PP‐
Module in which this SFR is defined] upon TOE power up and upon
connection of a peripheral device to a powered‐on TOE.
FDP_PDC_EXT.2.2 The TSF shall allow connections with authorized devices presenting
authorized interface protocols as defined in [assignment: devices
specified in the PP or PP Module in which this SFR is defined] and
[assignment: devices specified in another PP or PP‐Module that
shares a PP‐Configuration with the PP or PP‐Module in which this SFR
is defined] upon TOE power up and upon connection of a peripheral
device to a powered‐on TOE.
FDP_PDC_EXT.3 Authorized Connection Protocols
Hierarchical to: No other components.
Dependencies: FDP_PDC_EXT.1 Peripheral Device Connection
FDP_PDC_EXT.3.1 The TSF shall have interfaces for the [assignment: list of supported
protocols associated with physical and/or logical TSF interfaces]
protocols.
FDP_PDC_EXT.3.2 The TSF shall apply the following rules to the supported protocols:
[assignment: rules defining the handling for communications over
this protocol (e.g. any processing that must be done by the TSF
prior to transmitting it through the TOE, circumstances or frequency
with which the protocol is invoked)].
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 32 of 66
FDP_RDR_EXT Re-Enumeration Device
Rejection
Family Behavior
Components in this family define requirements to reject device spoofing
attempts through reenumeration.
Component Leveling
FDP_RDR_EXT.1 Re‐Enumeration Device Rejection, requires the TSF to reject re‐
enumeration as an unauthorized device.
Management: FDP_RDR_EXT.1
No specific management functions are identified.
Audit: FDP_RDR_EXT.1
There are no specific auditable events foreseen.
FDP_RDR_EXT.1 Re-Enumeration Device Rejection
Hierarchical to: No other components.
Dependencies: FDP_PDC_EXT.1 Peripheral Device Connection
FDP_RDR_EXT.1.1 The TSF shall reject any device that attempts to enumerate again as
a different unauthorized device.
FDP_RIP_EXT Residual Information Protection
Family Behavior
Components in this family define the requirements for how the TSF prevents
data disclosure from its memory.
Component Leveling
FDP_RDR_EXT Re-
Enumeration Device
Rejection
1
FDP_RIP_EXT Residual
Information Protection
1
2
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 33 of 66
FDP_RIP_EXT.1 Residual Information Protection, requires the TSF to prevent the
writing of user data to non‐volatile memory.
FDP_RIP_EXT.2 Purge of Residual Information, requires the TSF to have a purge
function to clear its memory of all stored non‐audit data.
Management: FDP_RIP_EXT.1, FDP_RIP_EXT.2
The following actions could be considered for the management functions in FMT:
• Ability to trigger the TSF’s purge function
Audit: FDP_RIP_EXT.1
There are no auditable events foreseen.
Audit: FDP_RIP_EXT.2
The following actions should be auditable if FAU_GEN.1 Audit Data Generation is
included in the PP/ST:
• Purging of the TSF’s memory
FDP_RIP_EXT.1 Residual Information Protection
Hierarchical to: No other components.
Dependencies: No dependencies
FDP_RIP_EXT.1.1 The TSF shall ensure that no user data is written to TOE non‐volatile
memory or storage.
FDP_RIP_EXT.2 Purge of Residual Information
Hierarchical to: No other components.
Dependencies: No dependencies
FDP_RIP_EXT.2.1 The TOE shall have a purge memory or restore factory defaults
function accessible to the administrator to delete all TOE stored
configuration and settings except for logging.
FDP_SPR_EXT Sub-Protocol Rules
Family Behavior
Components in this family define the sub‐protocols that the TSF allows or blocks
depending on the protocols it supports.
Component Leveling
FDP_SPR_EXT.1 Sub‐Protocol Rules, requires the TSF to specify the allowed and
blocked sub‐protocols based on the protocol it supports.
FDP_SPR_EXT Sub-
Protocol Rules
1
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 34 of 66
Management: FDP_SPR_EXT.1
No specific management functions are identified.
Audit: FDP_SPR_EXT.1
There are no auditable events foreseen.
FDP_SPR_EXT.1 Sub-Protocol Rules
Hierarchical to: No other components.
Dependencies: FDP_PDC_EXT.3 Authorized Connection Protocols
FDP_SPR_EXT.1.1 The TSF shall apply the following rules for the [assignment:
supported protocol] protocol:
• block the following video/display sub‐protocols:
o [assignment: list of blocked sub‐protocols]
• allow the following video/display sub‐protocols:
o [assignment: list of allowed sub‐protocols].
FDP_SWI_EXT PSD Switching
Family Behavior
Components in this family define the requirements for how the TSF protects
against inadvertent data switching.
Component Leveling
FDP_SWI_EXT.1 PSD Switching, requires action on the part of a user in order for
the TSF’s switching mechanisms to be activated.
FDP_SWI_EXT.2 PSD Switching Methods, places restrictions on how the TSF’s
switching mechanisms can be controlled.
FDP_SWI_EXT.3 Tied Switching, requires the TSF to ensure that multiple
connected peripherals are always switched to the same connected computer.
Management: FDP_SWI_EXT.1, FDP_SWI_EXT.2, FDP_SWI_EXT.3
No specific management functions are identified.
FDP_SWI_EXT PSD
Switching
1
2
3
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 35 of 66
Audit: FDP_SWI_EXT.1, FDP_SWI_EXT.2, FDP_SWI_EXT.3
There are no auditable events foreseen.
FDP_SWI_EXT.1 PSD Switching
Hierarchical to: No other components.
Dependencies: No dependencies
FDP_SWI_EXT.1.1 The TSF shall ensure that [selection: the TOE supports only one
connected computer, switching can be initiated only through express
user action].
FDP_SWI_EXT.2 PSD Switching Methods
Hierarchical to: No other components.
Dependencies: FDP_SWI_EXT.1 PSD Switching
FDP_SWI_EXT.2.1 The TSF shall ensure that no switching can be initiated through
automatic port scanning, control through a connected computer, or
control through keyboard shortcuts.
FDP_SWI_EXT.2.2 The TSF shall ensure that switching can be initiated only through
express user action using [selection: console buttons, console
switches, console touch screen, wired remote control, peripheral
devices using a guard].
FDP_SWI_EXT.3 Tied Switching
Hierarchical to: No other components.
Dependencies: FDP_SWI_EXT.1 PSD Switching
FDP_SWI_EXT.3.1 The TSF shall ensure that [assignment: two or more tied peripheral
devices] are always switched together to the same connected
computer.
FDP_UDF_EXT Unidirectional Data Flow
Family Behavior
Components in this family define unidirectional transmission of user data.
Component Leveling
FDP_UDF_EXT.1 Unidirectional Data Flow, requires the TSF to provide
unidirectional (one‐way) communications between a given pair of interface
types.
Management: FDP_UDF_EXT.1
No specific management functions are identified.
FDP_UDF_EXT
Unidirectional Data Flow
1
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 36 of 66
Audit: FDP_UDF_EXT.1
There are no auditable events foreseen.
FDP_UDF_EXT.1 Unidirectional Data Flow
Hierarchical to: No other components.
Dependencies: FDP_APC_EXT.1 Active PSD Connections
FDP_UDF_EXT.1.1 The TSF shall ensure [assignment: type of data] data transits the
TOE unidirectionally from the [assignment: origin point of data]
interface to the [assignment: destination point of data] interface.
5.2 CLASS FPT: PROTECTION OF THE TSF
FPT_FLS_EXT Failure with Preservation of
Secure State
Family Behavior
Components in this family define the secure failure requirements for the TSF.
Component Leveling
FPT_FLS_EXT.1 Failure with Preservation of Secure State, requires the TSF to go
into a secure state upon the detection of selected failures.
Management: FPT_FLS_EXT.1
No specific management functions are identified.
Audit: FPT_FLS_EXT.1
There are no auditable events foreseen.
FPT_FLS_EXT.1 Failure with Preservation of Secure State
Hierarchical to: No other components.
Dependencies: FPT_TST.1 TSF Testing
FPT_PHP.3 Resistance to Physical Attack
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 [selection: failure
of the anti‐tamper function, no other failures].
FPT_NTA_EXT No Access to TOE
Family Behavior
Components in this family define what TSF information may be externally
accessible.
FDP_FLS_EXT Failure with
Preservation of Secure
State
1
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 37 of 66
Component Leveling
FPT_NTA_EXT.1 No Access to TOE, requires the TSF to block access to non‐
authorized TSF data via external ports.
Management: FPT_NTA_EXT.1
No specific management functions are identified.
Audit: FPT_NTA_EXT.1
There are no auditable events foreseen.
FPT_NTA_EXT.1 No Access to TOE
Hierarchical to: No other components.
Dependencies: No dependencies
FPT_NTA_EXT.1.1 TOE firmware, software, and memory shall not be accessible via the
TOE’s external ports, with the following exceptions: [selection: the
EDID memory of Video TOEs may be accessible from connected
computers; the configuration data, settings, and logging data that
may be accessible by authorized administrators; no other
exceptions].
FPT_TST_EXT TSF Testing
Family Behavior
Components in this family define how the TSF responds to a self‐test failure.
Component Leveling
FPT_TST_EXT.1 TSF Testing, requires the TSF to shutdown normal functions and
provide a visual or auditory indication that a self‐test has failed.
Management: FPT_TST_EXT.1
No specific management functions are identified.
FPT_NTA_EXT No Access to
TOE
1
FPT_TST_EXT TSF Testing 1
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 38 of 66
Audit: FPT_TST_EXT.1
The following actions should be auditable if FAU_GEN.1 Audit Data Generation is
included in the PP/ST:
• Indication that the TSF self‐test was completed
• Failure of self‐test
FPT_TST_EXT.1 TSF Testing
Hierarchical to: No other components.
Dependencies: FPT_TST.1 TSF Testing
FPT_TST_EXT.1.1 The TSF shall respond to a self‐test failure by providing users with a
[selection: visual, auditory] indication of failure and by shutdown of
normal TSF functions.
5.3 CLASS FTA: TOE ACCESS
FTA_CIN_EXT Continuous Indications
Family Behavior
Components in this family define how the TSF displays its switching status.
Component Leveling
FTA_CIN_EXT.1 Continuous Indications, requires the TSF to display a visual
indication of what computers are selected.
Management: FTA_CIN_EXT.1
No specific management functions are identified.
Audit: FTA_CIN_EXT.1
There are no auditable events foreseen.
FTA_CIN_EXT.1 Continuous Indications
Hierarchical to: No other components.
Dependencies: FDP_APC_EXT.1 Active PSD Connections
FTA_CIN_EXT.1.1 The TSF shall display a visible indication of the selected computers
at all times when the TOE is powered.
FTA_CIN_EXT.1.2 The TSF shall implement the visible indication using the following
mechanism: easily visible graphical and/or textual markings
of each source video on the display, [selection: a button, a
panel with lights, a screen with dimming function, a screen with no
dimming function, [assignment: description of visible indication]].
FTA_CIN_EXT Continuous
Indications
1
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 39 of 66
FTA_CIN_EXT.1.3 The TSF shall ensure that while the TOE is powered the current
switching status is reflected by [selection: the indicator, multiple
indicators which never display conflicting information].
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 40 of 66
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. These
operations are shown using the same conventions as those in the PSD PP. This is
defined in the PP as:
• Assignment: Indicated by surrounding brackets and italics, e.g., [assigned
item].
• Selection: Indicated by surrounding brackets and italics, e.g., [selected
item].
• Refinement: Refined components are identified by using bold for
additional information, or strikeout for deleted text.
• Iteration: Iteration operations are identified with a slash (‘/’) and an
identifier (e.g. “/KM”).
Extended SFRs are identified by the inclusion of “EXT” in the SFR name.
6.2 SECURITY FUNCTIONAL REQUIREMENTS
The security functional requirements for this ST consist of the following
components.
Class Identifier Name
Security Audit (FAU) FAU_GEN.1 Audit data generation
User Data Protection
(FDP)
FDP_APC_EXT.1/KM Active PSD Connections
FDP_APC_EXT.1/VI Active PSD Connections
FDP_CDS_EXT.1 Connected Displays Supported
FDP_FIL_EXT.1/KM Device Filtering (Keyboard/Mouse)
FDP_PDC_EXT.1 Peripheral Device Connection
FDP_PDC_EXT.2/KM Authorized Devices (Keyboard/Mouse)
FDP_PDC_EXT.2/VI Authorized Devices (Video Output)
FDP_PDC_EXT.3/KM Authorized Connection Protocols
(Keyboard/Mouse)
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 41 of 66
Class Identifier Name
FDP_PDC_EXT.3/VI Authorized Connection Protocols
(Video Output)
FDP_RDR_EXT.1 Re-Enumeration Device Rejection
FDP_RIP_EXT.1 Residual Information Protection
FDP_RIP.1/KM Residual Information Protection
(Keyboard Data)
FDP_RIP_EXT.2 Purge of Residual Information
FDP_SPR_EXT.1/DVI-D Sub-Protocol Rules (DVI-D Protocol)
FDP_SWI_EXT.1 PSD Switching
FDP_SWI_EXT.2 PSD Switching Methods
FDP_SWI_EXT.3 Tied Switching
FDP_UDF_EXT.1/KM Unidirectional Data Flow
(Keyboard/Mouse)
FDP_UDF_EXT.1/VI Unidirectional Data Flow (Video
Output)
Identification and
Authentication (FIA)
FIA_UAU.2 User Authentication Before Any Action
FIA_UID.2 User Identification Before Any Action
Security
Management (FMT)
FMT_MOF.1 Management of Security Functions
Behavior
FMT_SMF.1 Specification of Management
Functions
FMT_SMR.1 Security Roles
Protection of the TSF
(FPT)
FPT_FLS_EXT.1 Failure with Preservation of Secure
State
FPT_NTA_EXT.1 No Access to TOE
FPT_PHP.1 Passive Detection of Physical Attack
FPT_PHP.3 Resistance to Physical Attack
FPT_STM.1 Reliable Time Stamps
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 42 of 66
Class Identifier Name
FPT_TST.1 TSF testing
FPT_TST_EXT.1 TSF Testing
TOE Access (FTA) FTA_CIN_EXT.1 Continuous Indications
Table 13 – Summary of Security Functional Requirements
Security Audit (FAU)
6.2.1.1 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 shutdown of the audit functions;
b. All auditable events for the [not specified] level of audit; and
c. [administrator login, administrator logout, self‐test failures, peripheral
device acceptance and rejections, [Restore to factory default, create
administrator account, change password].
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 (if
applicable), and the outcome (success or failure) of the event; and
b. For each audit event type, based on the auditable event definitions of
the functional components included in the PP/ST, [no other
information].
User Data Protection (FDP)
6.2.2.1 FDP_APC_EXT.1/KM Active PSD Connections
FDP_APC_EXT.1.1/KM The TSF shall route user data only to or from the interfaces
selected by the user.
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.
6.2.2.2 FDP_APC_EXT.1/VI Active PSD Connections
FDP_APC_EXT.1.1/VI The TSF shall route user data only to or from the interfaces
selected by the user.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 43 of 66
FDP_APC_EXT.1.2/VI 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/VI The TSF shall ensure that no data transits the TOE when the
TOE is powered off.
FDP_APC_EXT.1.4/VI The TSF shall ensure that no data transits the TOE when the
TOE is in a failure state.
6.2.2.3 FDP_CDS_EXT.1 Connected Displays Supported
FDP_CDS_EXT.1.1 The TSF shall support [one connected display] at a time.
6.2.2.4 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.
6.2.2.5 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.
6.2.2.6 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] and [
• authorized devices as defined in the PP‐Module for
Video/Display Devices
] upon TOE power up and upon connection of a peripheral
device to a powered-on TOE.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 44 of 66
FDP_ PDC_EXT.2.2/KM The TSF shall allow connections with authorized devices
presenting authorized interface protocols as defined in
[Appendix E] and [
• authorized devices presenting authorized interface
protocols as defined in the PP‐Module for
Video/Display Devices
] upon TOE power up and upon connection of a peripheral
device to a powered-on TOE.
6.2.2.7 FDP_PDC_EXT.2/VI Peripheral Device Connection
(Video Output)
FDP_PDC_EXT.2.1/VI The TSF shall allow connections with authorized devices as
defined in [Appendix E] and [
• authorized devices and functions as defined in the
PP‐Module for Keyboard/Mouse Devices,
] upon TOE power up and upon connection of a peripheral
device to a powered-on TOE.
FDP_ PDC_EXT.2.2/VI The TSF shall allow connections with authorized devices
presenting authorized interface protocols as defined in
[Appendix E] and [
• authorized devices presenting authorized interface
protocols as defined in the PP‐Module for
Keyboard/Mouse Devices,
] upon TOE power up and upon connection of a peripheral
device to a powered-on TOE.
6.2.2.8 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].
6.2.2.9 FDP_PDC_EXT.3/VI Authorized Connection Protocols
(Video Output)
FDP_PDC_EXT.3.1/VI The TSF shall have interfaces for the [DVI-D] protocols.
FDP_PDC_EXT.3.2/VI The TSF shall apply the following rules to the supported
protocols: [the TSF shall read the connected display EDID
information once during power‐on or reboot].
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 45 of 66
6.2.2.10 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.
6.2.2.11 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.
6.2.2.12 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.
6.2.2.13 FDP_RIP_EXT.2 Purge of Residual Information
FDP_RIP_EXT.2.1 The TOE shall have a purge memory or restore factory defaults
function accessible to the administrator to delete all TOE stored
configuration and settings except for logging.
6.2.2.14 FDP_SPR_EXT.1/DVI-D Sub-Protocol Rules (DVI-D
Protocol)
FDP_SPR_EXT.1.1/DVI-D The TSF shall apply the following rules for the [DVI-D]
protocol:
• block the following video/display sub‐protocols:
o [ARC,
o CEC,
o EDID from computer to display,
o HDCP,
o HEAC,
o HEC,
o MCCS]
• allow the following video/display sub‐protocols:
o [EDID from display to computer,
o HPD from display to computer].
6.2.2.15 FDP_SWI_EXT.1 PSD Switching
FDP_SWI_EXT.1.1 The TSF shall ensure that [switching can be initiated only through
express user action].
6.2.2.16 FDP_SWI_EXT.2 PSD Switching Methods
FDP_SWI_EXT.2.1 The TSF shall ensure that no switching can be initiated through
automatic port scanning, control through a connected computer, or
control through keyboard shortcuts.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 46 of 66
FDP_SWI_EXT.2.2 The TSF shall ensure that switching can be initiated only through
express user action using [console buttons, wired remote control].
6.2.2.17 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.
6.2.2.18 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.
6.2.2.19 FDP_UDF_EXT.1/VI Unidirectional Data Flow (Video
Output)
FDP_UDF_EXT.1.1/VI The TSF shall ensure [video] data transits the TOE
unidirectionally from the [TOE computer video] interface to the
[TOE peripheral device display] interface.
Identification and Authentication
6.2.3.1 FIA_UAU.2 User Authentication Before Any Action
FIA_UAU.2.1 The TSF shall require each administrator to be successfully
authenticated before allowing any other TSF-mediated actions on behalf
of that administrator.
6.2.3.2 FIA_UID.2 User Identification Before Any Action
FIA_UID.2.1 The TSF shall require each administrator to be successfully identified
before allowing any other TSF-mediated actions on behalf of that
administrator.
Security Management (FMT)
6.2.4.1 FMT_MOF.1 Management of Security Functions Behavior
FMT_MOF.1.1 The TSF shall restrict the ability to [modify the behavior of] the
functions [Restore to factory default] to [the authorized administrator].
6.2.4.2 FMT_SMF.1 Specification of Management Functions
FMT_SMF.1.1 The TSF shall be capable of performing the following management
functions: [Restore to factory default, create administrator account,
change password].
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 47 of 66
6.2.4.3 FMT_SMR.1 Security roles
FMT_SMR.1.1 The TSF shall maintain the roles [administrators].
FMT_SMR.1.2 The TSF shall be able to associate users with roles.
Protection of the TSF (FPT)
6.2.5.1 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 [failure of the
antitamper function].
6.2.5.2 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: [the Extended
Display Identification Data (EDID) memory of Video TOEs may
be accessible from connected computers; the configuration data,
settings, and logging data that may be accessible by authorized
administrators].
6.2.5.3 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.
6.2.5.4 FPT_PHP.3 Resistance to Physical Attack
FPT_PHP.3.1 The TSF shall resist [a physical attack for the purpose of gaining access
to the internal components, to damage the anti‐tamper battery, to drain
or exhaust the anti‐tamper battery] to the [TOE enclosure and any
remote controllers] by the attacked component becoming permanently
disabled.
6.2.5.5 FPT_STM.1 Reliable Time Stamps
Hierarchical to: No other components.
Dependencies: No dependencies.
FPT_STM.1.1 The TSF shall be able to provide reliable time stamps.
6.2.5.6 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 [active anti-tamper
functionality]].
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 48 of 66
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].
6.2.5.7 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.
TOE Access (FTA)
6.2.6.1 FTA_CIN_EXT.1 Continuous Indications
FTA_CIN_EXT.1.1 The TSF shall display a visible indication of the selected computers
at all times when the TOE is powered.
FTA_CIN_EXT.1.2 The TSF shall implement the visible indication using the following
mechanism: easily visible graphical and/or textual markings
of each source video on the display, [[illuminated buttons]].
FTA_CIN_EXT.1.3 The TSF shall ensure that while the TOE is powered the current
switching status is reflected by [multiple indicators which never
display conflicting information].
6.3 SECURITY ASSURANCE REQUIREMENTS
The assurance requirements are summarized in Table 14.
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
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 49 of 66
Assurance Class
Assurance Components
Identifier Name
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 14 – Security Assurance Requirements
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 50 of 66
6.4 SECURITY REQUIREMENTS RATIONALE
Security Functional Requirements Rationale
Table 9 provides a mapping between the SFRs and Security Objectives.
Dependency Rationale
Table 15 identifies the Security Functional Requirements and their associated
dependencies. It also indicates whether the ST explicitly addresses each
dependency.
SFR Dependencies Rationale Statement
FAU_GEN.1 FPT_STM.1 Included
FDP_APC_EXT.1/KM None N/A
FDP_APC_EXT.1/VI None N/A
FDP_CDS_EXT.1 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.2/VI FDP_PDC_EXT.2 Included
FDP_PDC_EXT.3/KM FDP_PDC_EXT.1 Included
FDP_PDC_EXT.3/VI FDP_PDC_EXT.2 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_RIP_EXT.2 None N/A
FDP_SPR_EXT.1/DVI-D FDP_PDC_EXT.3 Included
FDP_SWI_EXT.1 None N/A
FDP_SWI_EXT.2 FDP_SWI_EXT.1 Included
FDP_SWI_EXT.3 FDP_SWI_EXT.1 Included
FDP_UDF_EXT.1/KM FDP_APC_EXT.1 Included
FDP_UDF_EXT.1/VI FDP_APC_EXT.1 Included
FIA_UAU.2 FIA_UID.1 Included
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 51 of 66
SFR Dependencies Rationale Statement
FIA_UID.2 None N/A
FMT_MOF.1 FMT SMF.1
FMT_SMR.1
Included
Included
FMT_SMF.1 None N/A
FMT_SMR.1 FIA_UID.1 Included
FPT_FLS_EXT.1 FPT_TST.1
FPT_PHP.3
Included
Included only 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_PHP.3 None N/A
FPT_STM.1 None N/A
FPT_TST.1 None N/A
FPT_TST_EXT.1 FPT_TST.1 Included
FTA_CIN_EXT.1 FDP_APC_EXT.1 Included
Table 15 – 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].
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 52 of 66
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 SECURITY AUDIT
The TOE is equipped with non-volatile memory for the storage of audit records.
There are two separate storage areas:
• Critical One Time Programming (OTP) Logs
o Self-test failure – a record of the latest self-test failure is recorded
with error code information
o Peripheral device rejection
o Restore to factory default event
o Changes to the primary administrator password
• Non-critical (Random Access Memory (RAM)) Logs
o Peripheral device acceptance
o Non-security related configuration changes
o Administrator login
o Administrator logout
o Creation and removal of administrator accounts
o Administrator password changes (other than for the primary
administrator)
All events include the date and time. Where applicable, the username of the
administrator who initiated the action is also recorded.
Logs cannot be deleted by the administrator. The critical logs hold up to 64
events. The non-critical logs hold up to 128 events. In both log files, the oldest
logs are overwritten when the storage space allocated to the logs becomes full.
Audit records can only be read by authorized administrators through the TOE
device’s terminal mode. Instructions for logging into the device and entering
terminal mode are detailed in the HSL Administrator Guide [HSL Admin].
TOE Security Functional Requirements addressed: FAU_GEN.1.
7.2 USER DATA PROTECTION
System Controller
The TOE includes a System Controller which is responsible for device
management, user interaction, system control security functions, and device
monitoring. It receives user input from the buttons on the front panel or from
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 53 of 66
the wired remote control, and drives the TOE channel select lines that control
switching circuits within the TOE.
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.
Following boot up of the TOE, the channel select lines are set to Channel 1 by
default. The channel select lines are also used to link the System Controller
channel select commands to the Field Programmable Gate Array (FPGA) that
supports video processing.
The user determines the host computer to be connected to the peripherals by
pressing a button on the TOE front panel or on the wired remote control device.
The front panel button of the selected computer is illuminated. Switching can
only be initiated through express user action.
TOE Security Functional Requirements addressed: FDP_SWI_EXT.1,
FDP_SWI_EXT.2.
7.2.1.1 Active PSD Connections
The TOE ensures that data flows only between the peripherals and the
connected computer selected by the user. 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,
FDP_APC_EXT.1/VI.
7.2.1.2 Connected Computer Interfaces
The connected computers are attached to the TOE as follows:
• The TOE connects to the keyboard and mouse port using a ruggedized 32
pin cable that supports USB.
• The TOE is connected to the computer video port using a ruggedized 32
pin cable that supports DVI-D video
TOE Security Functional Requirements addressed: FDP_PDC_EXT.1.
7.2.1.3 Residual Information Protection
The Letter of Volatility is included as Annex A.
A Restore to Factory Default (RFD) action may be initiated by an authorized
administrator through the administration console, or by selecting Left Ctrl |
Left Ctrl | f11 | r from the keyboard of the connected computer.
When the RFD command is issued, it initiates the following actions:
• All peripheral devices are logically disconnected from the selected
computer
• The front panel LEDs blink together
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 54 of 66
• The TOE resets, purging the appropriate data
• The TOE performs a normal power up and self-test sequence
When the device completes the reboot, the peripherals will be connected to
channel #1 and all default settings will be restored. The data in the critical logs,
and the primary administrator username and password data are maintained in
the OTP Memory of the System Controller.
TOE Security Functional Requirements addressed: FDP_RIP_EXT.1,
FDP_RIP_EXT.2.
Keyboard and Mouse Functionality
7.2.2.1 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 hosts, 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 peripheral sharing device, and when the user switches
channels. When the TOE switches from one computer to another, the system
controller ensures that the keyboard and mouse stacks are deleted, and that
any data received from the keyboard in the first 100 milliseconds following
switching is deleted. This is done to ensure that any data buffered in the
keyboard microcontroller is not passed to the newly selected computer.
The TOE supports USB 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 hosts.
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.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 55 of 66
TOE Security Functional Requirements addressed: FDP_PDC_EXT.3/KM,
FDP_UDF_EXT.1/KM, FDP_RIP.1/KM.
7.2.2.2 Keyboard and Mouse Switching Functionality
Figure 4 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 key strokes
into unidirectional serial data.
Figure 4 – Simplified Switching Diagram
The combined data stream is passed through the channel select lines to the
selected host channel. The channel select lines are driven by the System
Controller Module, and the selection is based on user input through use of the
mouse or keyboard. Once a channel is selected, the combined mouse and
keyboard data stream is passed through an optical data diode and routed to the
specific host channel device emulator. The optical data diode is an opto-coupler
designed to physically prevent reverse data flow. The keyboard and mouse can
only be switched together.
Device emulators are USB enabled microcontrollers that are programmed to
emulate a standard USB keyboard and mouse composite device. The combined
data stream is converted back to bidirectional data before reaching the selected
host computer.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 56 of 66
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.
TOE Security Functional Requirements addressed: FDP_APC_EXT.1/KM,
FDP_UDF_EXT.1/KM, FDP_SWI_EXT.3.
7.2.2.3 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 connections over custom 32 pin
ruggedized cables 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.
7.2.2.4 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.
TOE Security Functional Requirements addressed: FDP_RDR_EXT.1.
Video Switching Functionality
Video data flow is comprised of unidirectional Extended Display Identification
Data (EDID) and video data flow paths. Figure 5 shows a data flow during the
display EDID read function.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 57 of 66
Figure 5 – Display EDID Read Function
An EDID read event only occurs as the TOE is being powered up. The video
controller reads the EDID content from the display device to verify that it is valid
and usable. If data is not valid, TOE operation will cease and wait for the display
peripheral to be changed.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 58 of 66
Figure 6 – Display EDID Write Function
Figure 6 illustrates the video controller (shown in blue) as it writes the EDID
content into the first channel emulated EDID Electrically Erasable Programmable
Read-Only Memory (EEPROM) chip (shown in gray). The thick lines in this figure
indicate native video lines, and the thin lines indicate Inter-Integrated Circuit
(I2C) lines. The EDID multiplexer couples the I2C lines to the first EDID mode
switch (shown in orange). The first EDID mode switch switches the video
controller I2C lines to the first emulated EDID EEPROM chip (shown in gray).
The chip write protect switch opens to enable writing. The video controller uses
the I2C lines to write to the first emulated EDID EEPROM chip. Once the write
operation is complete and verified, the video controller switches the EDID
multiplexer to the next channel and the operation repeats until all chips are
programmed. Once the write operation is complete, the video controller switches
to normal operating mode, as shown in Figure 7 below.
In EDID write mode, the Emulated EDID EEPROM chips are switched to their
respective computers to enable reading of the EDID information. The write
protect switches are switched back to protected mode to prevent any attempt to
write to the EEPROM or to transmit MCCS commands.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 59 of 66
Figure 7 – Display Normal Mode
In normal mode, each computer interface operates independently. The power to
each emulated EDID EEPROM is received from its respective computer through
the video cable. The main video multiplexer is switched to the user selected
computer to enable the proper video display.
During TOE normal operation (Figure 7), any attempt by a connected computer
to affect the EDID channel is blocked by the architecture. Each computer is only
able to affect its own emulated EDID EEPROM.
Video input interfaces are isolated from one another. Isolation is achieved
through the use of separate power and ground planes, separate electronic
components and a separate emulated EDID chip for each channel.
The EDID function is emulated by an independent emulation EEPROM chip for
each computer channel. These chips read content from the connected display
once during TOE power up. Any subsequent change to the display peripheral will
be ignored.
The TOE will reject any display device that does not present valid EDID content.
An LED on the rear panel of the TOE will indicate a rejected display device.
The TOE supports DVI-D video. EDID information is allowed to pass from the
display to the computer, as described above. Hot-Plug Detection (HPD)
information is also allowed to pass. Other protocols, including Audio Return
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 60 of 66
Channel (ARC), EDID from the computer to the display, HDMI Ethernet and
Audio Return Channel (HEAC), HDMI Ethernet Channel (HEC) and MCCS are
blocked. High-bandwidth Digital Content Protection (HDCP) and Consumer
Electronics Control (CEC) functions are not connected
The TOE video function blocks MCCS write transactions through the emulated
EDID EEPROMs. The emulated EEPROMs support only EDID read transactions,
and are isolated by the write protect switch.
Following triggering of the anti-tampering function, following a failed self-test, or
when the TOE is powered off, all video input signals are isolated from other
video inputs and from the video output interfaces by the active video re-drivers.
Emulated EDID EEPROMs may still operate since they are powered by their
respective computers; however, the video function remains isolated.
TOE Security Functional Requirements addressed: FDP_SPR_EXT.1/DVI-D,
FDP_UDF_EXT.1/VI.
7.2.3.1 Video Compatible Device Types
The TOE accepts any DVI-D display device at the video peripheral port. The TOE
does not support a wireless connection to a video display.
A single video display is supported.
TOE Security Functional Requirements addressed: FDP_PDC_EXT.1,
FDP_PDC_EXT.2/VI, FDP_PDC_EXT.3/VI, FDP_CDS_EXT.1.
7.3 IDENTIFICATION AND AUTHENTICATION
AND SECURITY MANAGEMENT
In order to access administrative functions, a user must be in possession of an
administrator username and password. A single administrator role is supported
by the TOE.
Administrators authenticate to the TOE by entering a username and password.
The default administrator username is ‘admin1234’. The primary administrator
account cannot be deleted. The password remains the same and does not revert
to the default when a Restore to Factory Default (RFD) operation is performed.
Up to nine additional administrator accounts may be created. These additional
accounts and associated passwords are removed when an RFD is performed. For
these accounts, usernames must be between 8 and 11 characters in length, and
may be made up of uppercase and lowercase letters.
The default administrator password is ‘1234ABCDefg!@#’, and must be changed
on the first login. Administrator passwords must be between 8 and 15 characters
in length and may contain uppercase letters, lowercase letters, numbers or any
of the following special characters: ‘!’, ‘@’, ‘#’, ‘$’, ‘%’, ‘^’, ‘&’, ‘*’, ‘(’, ‘)’, ‘-’, or
‘_’. The password must contain at least one uppercase letter, one lowercase
letter, one number and one special character.
Passwords are stored in the non-volatile memory in a proprietary, obfuscated
format.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 61 of 66
Lost usernames or passwords cannot be recovered. The user is locked out after
three failed login attempts. The user may cycle the device power and try again.
Once logged in, the administrator may use the functions described in the [HSL
Admin] to manage the TOE configuration. The administrator login and any
configuration changes made are recorded in the audit logs along with the date
and time of the event.
The administrator can use the administrator console function to perform the
following tasks:
• Manage administrator accounts (change password, create administrator
account)
• Restore to factory defaults – note that this does not reset the username
and password of the primary administrator, and does not reset the critical
logs
TOE Security Functional Requirements addressed: FIA_UAU.2, FIA_UID.2,
FMT_MOF.1, FMT_SMF.1, FMT_SMR.1.
7.4 PROTECTION OF THE TSF
No Access to TOE
Connected computers do not have access to TOE firmware or memory, with the
following exceptions:
• EDID data is accessible to connected computers from the TOE
• Authorized administrators use a connected computer to access
configuration data and settings
• Authorized administrators use a connected computer to access TOE audit
records
All of the TOE microcontrollers run 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.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 62 of 66
Anti-tampering Functionality
The TOE provides both passive and active anti-tampering functionality.
7.4.2.1 Passive Detection of Physical Tampering
The TOE enclosure was designed specifically to prevent physical tampering. It
features a stainless-steel welded chassis and panels that prevent external access
through bending or brute force.
Additionally, the device is fitted with 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. The remote
control also has a holographic Tampering Evident Label placed at a critical
location.
TOE Security Functional Requirements addressed: FPT_PHP.1.
7.4.2.2 Resistance to Physical Attack
The anti-tampering system is mechanically coupled to the switch enclosure to
detect any attempt to access the TOE internal circuitry. Any attempt to separate
the pieces of the enclosure to access the internal circuitry will trigger the anti-
tampering function. Power is provided to the circuitry by the TOE power supply
and by a backup battery. If the self-test detects that the battery is depleted or
failing, the anti-tampering function will be triggered.
When the anti-tampering function is triggered, is causes an internal microscopic
fuse on the System Controller (on-die) to melt. This permanently disables all
interfaces and user functions of the device, and causes the front panel LEDs to
blink sequentially and continuously. The TOE anti-tampering function is
irreversible.
When the anti-tampering mechanism on the KVM switch is triggered, an event is
recorded in the TOE internal non-volatile memory with the time and date. This
record may be read from the audit logs.
When the anti-tampering mechanism on the remote control is triggered, the
device becomes permanently disabled.
TOE Security Functional Requirements addressed: FPT_FLS_EXT.1, FPT_PHP.3.
Reliable Timestamps
Each device includes a real-time clock powered by a battery. The purpose of the
clock is to provide an accurate timestamp for audited events. The time is set
during production using the Central Time Zone. Administrators are not permitted
to modify the time. Time is not provided to external devices, so there is no
requirement to coordinate time zones or change to daylight savings time. The
battery is designed to power the unit for a minimum of ten years. If the battery
fails, the device enters the tampered mode. The user must then replace the
device.
TOE Security Functional Requirements addressed: FPT_STM.1.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 63 of 66
TSF Testing
The TOE performs a self-test at initial start-up. The self-test runs independently
at each microcontroller and performs the following checks:
• Verification of the front panel push-buttons
• Verification of the active anti-tampering functionality, including the
continued functionality of the backup battery
• Verification of the integrity of the microcontroller firmware
• Verification of computer port isolation. This is tested by sending test
packets to various interfaces and attempting to detect this traffic at all
other interfaces
If the self-test fails, the LEDs on the front panel blink and the device makes a
clicking sound to indicate the failure. The TOE disables the PSD switching
functionality, and remains in a disabled state until the self-test is rerun and
passes.
TOE Security Functional Requirements addressed: FPT_FLS_EXT.1, FPT_TST.1,
FPT_TST_EXT.1.
7.5 TOE ACCESS
The TOE user switches between computers by pressing the corresponding front
panel button on the device, or on the remote control. The front panel button
corresponding to the selected computer will illuminate.
On power up or power up following reset, all peripherals are connected to
channel #1, and the corresponding push button LED will be illuminated.
TOE Security Functional Requirements addressed: FTA_CIN_EXT.1.
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 64 of 66
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.
VI VI refers to the requirements for Video/Display Devices.
Table 16 – Terminology
8.2 ACRONYMS
The following acronyms are used in this ST:
Acronym Definition
ARC Audio Return Channel
CC Common Criteria
CEC Consumer Electronics Control
DE Device Emulator
DVI Digital Visual Interface
EDID Extended Display Identification Data
EEPROM Electrically Erasable Programmable Read-Only Memory
FPGA Field Programmable Gate Array
HDCP High-bandwidth Digital Content Protection
HE Host Emulator
HEAC HDMI Ethernet and Audio Return Channel
HEC HDMI Ethernet Channel
HID Human Interface Device
HPD Hot-Plug Detection
HSL High Sec Labs
I2C Inter-Integrated Circuit
IT Information Technology
JTAG Joint Test Action Group
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 65 of 66
Acronym Definition
KVM Keyboard, Video, Mouse
LED Light Emitting Diode
MCCS Monitor Control Command Set
NIAP National Information Assurance Partnership
OTP One Time Programming
PP Protection Profile
PSD Peripheral Sharing Device
RAM Random Access Memory
RFD Restore to Factory Default
ROM Read Only Memory
SFR Security Functional Requirement
SRAM Static Random Access Memory
ST Security Target
TOE Target of Evaluation
TSF TOE Security Functionality
USB Universal Serial Bus
VDC Volts Direct Current
Table 17 – Acronyms
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page 66 of 66
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
[HSL Admin] HSL Administrator Guide, Revision C
[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
[MOD_VI_1.0] PP‐Module for Video/Display Devices, Version 1.0, 2019‐07‐19
[CFG_PSD‐KM‐
VI_V1.0]
PP‐Configuration for Peripheral Sharing Device,
Keyboard/Mouse Devices, and Video/Display Devices, 19 July
2019
Table 18 – References
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page A-1 of A-2
ANNEX A – LETTER OF VOLATILITY
The table below provides volatility information and memory types for the High Sec Labs SK41D-4TR Peripheral
Sharing Device. User data is not retained when the power is turned off.
Product
Model
Number
in each
product
Function,
Manufacturer
and Part
Number
Storage Type Size Power
Source (if
not the TOE)
Volatility Contains
User Data
Effect of RFD
SK41D-4TR 1 System Controller,
Host emulators:
ST Microelectronics
STM32F446ZCT
Embedded SRAM1
128KB Connected
computer
Volatile May contain user
data
Data is purged
Embedded Flash2
256KB Non-Volatile No user data Firmware is
retained
Embedded EEPROM 4KB Non-Volatile No user data Data is purged
on RFD
OTP Memory 512bytes Non-Volatile No user data Log data is
retained
5 Video Controller:
ST Microelectronics
STM32F070C6T6
Embedded SRAM1
16KB Connected
computer
Volatile No user data Data is purged
Embedded Flash2
128KB Non-Volatile No user data Firmware is
retained
Embedded EEPROM 4KB Non-Volatile No user data Data is purged
on RFD
4 Device emulators:
ST Microelectronics
STM32F070C6T6
Embedded SRAM1
6KB Connected
computer
Volatile May contain user
data
Data is purged
Embedded Flash2
32KB Non-Volatile No user data Firmware is
retained
Embedded EEPROM 4KB Non-Volatile No user data Data is purged
on RFD
Table 19 – Letter of Volatility
High Sec Labs SK41D-4TR KVM
Security Target
Doc No: 2149-001-D102A5 Version: 1.7 Date: 14 September 2021 Page A-2 of A-2
Notes:
1
SRAM stores USB Host stack parameters and up to the last 4 key-codes. Data is erased during power off of the KVM, and
when the user switches channels. Device emulators receive power from the individual connected computers 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 ST Microcontroller together with SRAM and EEPROM.