Sekuryx Secure KVM Switch Security Target (Non-CAC Models) Rev 1.06
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Sekuryx Secure KVM Switch Security
Target (Non-CAC Models)
Release Date: August 20, 2021
Revision: 1.06
Author: Steve Barash, Sekuryx
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Table of Contents
1 Introduction...........................................................................................................................6
1.1 ST and TOE Identification.................................................................................................. 6
1.2 PP Reference Identification............................................................................................... 6
1.3 Organization ....................................................................................................................... 7
1.4 Conventions ........................................................................................................................ 8
1.5 Technical Definitions ......................................................................................................... 8
1.5.1 ST Specific Terminology............................................................................................. 8
1.5.2 Acronyms................................................................................................................... 11
1.6 TOE Overview................................................................................................................... 12
1.6.1 TOE Architecture (High Level) ................................................................................ 12
1.6.2 TOE Details ................................................................................................................ 13
1.7 TOE Scope and Boundary ................................................................................................ 19
1.7.1 Overview.................................................................................................................... 19
1.7.2 Environment.............................................................................................................. 21
1.8 Guidance Documents ....................................................................................................... 21
1.9 Features Outside of TOE Evaluation Scope.................................................................... 21
2 Security Problem Description ...................................................................................... 22
2.1 Assumptions ..................................................................................................................... 22
2.2 Organizational Security Policies ..................................................................................... 23
2.3 Threats .............................................................................................................................. 23
3 Security Objectives........................................................................................................... 25
3.1 Security Objectives for the TOE ...................................................................................... 25
3.2 Security Objectives for the Operational Environment.................................................. 27
4 Security Requirements.................................................................................................... 29
4.1 TOE Security Functional Requirements ......................................................................... 29
4.1.1 Overview.................................................................................................................... 29
4.1.2 Class FAU: Security Audit ......................................................................................... 31
4.1.3 Class FDP: User Data Protection.............................................................................. 32
4.1.4 Class FIA: Identification and Authentication.......................................................... 38
4.1.5 Class FMT: Security Management............................................................................ 38
4.1.6 Class FPT: Protection of the TSF.............................................................................. 38
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4.1.7 Class FTA: TOE Access.............................................................................................. 40
4.2 Rationale for TOE Security Requirement Dependencies .............................................. 40
4.3 TOE Security Assurance Requirements.......................................................................... 41
5 Conformance Claims........................................................................................................ 42
5.1 CC Conformance Claims................................................................................................... 42
5.2 PP Conformance Claims................................................................................................... 42
5.3 ST Conformance Requirements ...................................................................................... 42
6 TOE Summary Specification.......................................................................................... 44
6.1 TOE External Interfaces Security Functions .................................................................. 44
6.2 TOE Administration, User Control, and Monitoring Security Functions ..................... 44
6.3 TOE Tampering Protection.............................................................................................. 46
6.4 TOE Self-Testing............................................................................................................... 47
6.5 TOE Audio Subsystem Security Functions ..................................................................... 48
6.6 TOE Keyboard and Mouse Functionality........................................................................ 49
6.7 TOE Video Subsystem Security Functions ..................................................................... 51
Appendix A – Product’s Model Name Structure............................................................. 55
Appendix B – Letter of Volatility ......................................................................................... 56
Main PCBA: USB ........................................................................................................................ 56
Video PCBA: DP.......................................................................................................................... 58
Front Panel PCBA ........................................................................................................................ 59
Table of Figures
Figure 1: Standard Setup of 2-Port KVM TOE Installation .......................................................... 20
Figure 2: Standard Setup of 4-Port TOE installation.................................................................... 20
List of Tables
Table 1 – ST Composition................................................................................................................. 6
Table 2 – ST Identification................................................................................................................ 6
Table 3 – ST Technical Definitions ................................................................................................ 11
Table 4 – ST Acronyms ................................................................................................................... 12
Table 5 – Sekuryx 2-Port Secure TOE Identification.................................................................... 13
Table 6 – Sekuryx 4-Port Secure TOE Identification.................................................................... 13
Table 7 – Sekuryx 8-Port Secure TOE Identification.................................................................... 13
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Table 8 – Peripheral Devices supported by the TOE ................................................................... 14
Table 9 – Console Port Protocols (2-Port TOE models) .............................................................. 14
Table 10 – Console Port Protocols (4-Port TOE models)............................................................ 15
Table 11 – Console Port Protocols (8-Port TOE models)............................................................ 15
Table 12 – Computer Port Protocols (2-Port TOE models) ........................................................ 15
Table 13 – Computer Port Protocols (4-Port TOE models) ........................................................ 16
Table 14 – Computer Port Protocols (8-Port TOE models) ........................................................ 16
Table 15 – TOE Services ................................................................................................................. 16
Table 16 – TOE Administrator Services and Accessibility........................................................... 17
Table 17 – TOE Physical Boundary Composition......................................................................... 19
Table 18 – TOE Components.......................................................................................................... 21
Table 19 – Environment Components........................................................................................... 21
Table 20 – Assumptions ................................................................................................................. 23
Table 21 – Threats .......................................................................................................................... 24
Table 22 – Security Objectives for the TOE................................................................................... 27
Table 23 – Security Objectives for the Operational Environment .............................................. 28
Table 24 – TOE SFR Overview ....................................................................................................... 31
Table 25 – Audio Filtration Specifications.................................................................................... 32
Table 26 – TOE Security Assurance Requirements...................................................................... 41
Table 27 – EDID Read/Write Time Chart...................................................................................... 52
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Document Revisions
Revision# Date By Updates
1.00 June 5, 2020 Steve Barash, Sekuryx Initial Document Outline
1.01 July 7, 2020 Steve Barash, Sekuryx Formatting updates and adding NIAP TDs
1.02
August 1,
2020
Steve Barash, Sekuryx
Responding to comments based on preliminary
evaluation
1.03
January 21,
2021
Steve Barash, Sekuryx
Separated requirements based on different
supported video protocols
1.04 May 21, 2021 Steve Barash, Sekuryx
Incorporation of NIAP feedback and
finalization
1.05
August 6,
2021
Steve Barash, Sekuryx Incorporation of evaluator feedback
1.06
August 20,
2021
Steve Barash, Sekuryx Incorporation of NIAP feedback
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1 Introduction
This section identifies the Security Target (ST), Target of Evaluation (TOE), conformance claims, ST
organization, document conventions, and terminology. It also includes an overview of the evaluated
product.
The composition of the ST is listed in the table below.
No. Security Target Composition
1
A security problem described as a set of assumptions about the security aspects of the
environment (see Chapter 2, Security Problem Description).
2
A set of threats which the product is proposed to identify and counter (see Chapter 2,
Security Problem Description).
3
Known rules which the product must comply to (see Chapter 2, Security Problem Description
and Chapter 5, Conformance Claims).
4
A set of security objectives to address the security problem (see Chapter 3, Security
Objectives).
5
A set of security requirements to address the security problem (see Chapter 4, Security
Requirements and Chapter 6, Extended Components Definition).
6
The IT security functions provided by the TOE that meet the set of requirements (see Chapter
7, TOE Summary Specification).
Table 1 – ST Composition
The structure and content of this ST complies with the requirements stated in the Common Criteria
(CC), Part 1, Annex A, and Part 3, Chapter 11.
1.1 ST and TOE Identification
This section provides information needed to identify and control this ST and its Target of Evaluation
(TOE).
ST Title Sekuryx Secure KVM Switch Security Target (Non-CAC Models)
Revision Number 1.06
ST Publish Date August 20, 2021
ST Authors Steve Barash, Sekuryx
TOE Identification See Tables 5, 6 and 7 below
Keywords KVM, Secure, Sekuryx, Protection Profile 4.0
Table 2 – ST Identification
1.2 PP Reference Identification
The TOE claims conformance to the following PP-Configuration:
PP-Configuration Reference: PP-Configuration for Peripheral Sharing Device, Analog Audio
Output Devices, Keyboard/Mouse Devices, and Video/Display Devices (CFG_PSD-AO-KM-VI_V1.0)
PP-Configuration Sponsor: National Information Assurance Partnership (NIAP)
PP-Configuration Version: 1.0
PP-Configuration Date: July 19, 2019
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The claimed PP-Configuration consists of the Base-PP referenced below and PP-Modules that
define required functionality and evaluation activities for the specific peripheral types supported
by the TOE.
PP Reference: Protection Profile for Peripheral Sharing Device
PP Sponsor: National Information Assurance Partnership (NIAP)
PP Version: 4.0
PP Date: July 19, 2019
PP-Module Reference: PP-Module for Analog Audio Output Devices
PP-Module Sponsor: National Information Assurance Partnership (NIAP)
PP-Module Version: 1.0
PP-Module Date: July 19, 2019
PP-Module Reference: PP-Module for Keyboard/Mouse Devices
PP-Module Sponsor: National Information Assurance Partnership (NIAP)
PP-Module Version: 1.0
PP-Module Date: July 19, 2019
PP-Module Reference: PP-Module for Video/Display Devices
PP-Module Sponsor: National Information Assurance Partnership (NIAP)
PP-Module Version: 1.0
PP-Module Date: July 19, 2019
1.3 Organization
Security Target Introduction (Section 1)
• Identification of the TOE and ST
• Overview of the TOE
• Overview of the content of the ST, document conventions, relevant terminology
• Description of the TOE security functions
• Physical and logical boundaries for the TOE
• Hardware and software that make up the TOE
Security Problem Description (Section 2)
• Threat List
• Set of organizational security policies
• Set of TOE and TOE environment assumptions
Security Objectives (Section 3)
• List of Security objectives for the TOE and TOE environment
• Description of how Security Objectives can be trusted to counter the threats identified for the
TOE.
Security Requirements (Section 4)
• List of Security Functional Requirements (SFRs) met by the TOE
• Security Functional Requirements exposition
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• List of Security Assurance Requirements (SARs) met by the TOE
• Security Assurance Requirements (SARs) exposition
Conformance Claims (Section 5)
• Applicable Common Criteria (CC) conformance claims
• Protection Profile (PP) conformance claims
• Assurance Package conformance claims
Summary Specification (Section 6)
• List of Security functions provided by the TOE
• How the Security functions satisfy the SFRs.
• List of Security assurance measures for the TOE
• Security assurance measures exposition
1.4 Conventions
The Common Criteria (CC) defines operations on Security Functional Requirements: assignments,
selections, assignments within selections and refinements. This document uses the following font
conventions to identify the operations defined by the CC:
• Assignment: Indicated with italicized text;
• Refinement made by ST author (refinements reproduced as-is from the PP are not formatted
as such): Indicated with added/substituted text in bold text and deletions with strikethroughs,
if necessary;
• Selection: Indicated with underlined text;
• Assignment within a Selection (or vice versa): Indicated with italicized and underlined text;
• Iteration: Indicated by appending the SFR name with a slash followed by text that uniquely
references the iteration (e.g. FDP_PDC_EXT.2/KM for an iteration of the FDP_PDC_EXT.2 SFR
that applies specifically to keyboard/mouse functionality)
Extended SFRs are identified with the label “_EXT” after the requirement name.
In cases where the claimed PP or Module has already completed an operation, the formatting used by
the PP or Module is preserved in the ST. Specifically, all completed operations are formatted as italicized
text and with the original open/closing brackets preserved.
1.5 Technical Definitions
See CC Part 1 Section 4 for definitions of common CC terms.
1.5.1 ST Specific Terminology
Term Description
Active
Interface/Connection
An Interface between a PSD and Device that currently has user
data flowing through it.
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Administrator
A person who administers (e.g., installs, configures, updates,
audits, maintains) a PSD, Connected Peripherals, and
Connections.
Analog Audio
Data stream that uses voltage to describe a continuous sound
wave.
Analog Audio Output
Computer Interface, or
Computer Interface
The Connector on a PSD through which analog audio data enters
the PSD from a Connected Computer.
Analog Audio Output
Peripheral Interface,
or Peripheral
Interface
The Connector on a PSD through which analog audio data exits
the PSD bound for a peripheral device.
Attenuation
A reduction in signal strength commonly occurring while
transmitting analog or digital signals over long distances.
Audio codec
PC subsystem capable of encoding and decoding a digital data
stream of audio.
Audio Output
Peripheral Device
Speakers, handset, and earphones.
Authorized Peripheral
A Peripheral Device that is both technically supported and
administratively permitted to have an active interface with the
PSD.
Blacklist
List containing one or more device attributes that will cause the
PSD to reject the devices having that attribute.
Combiner (multi-
viewer)
A PSD with video integration functionality. Used to
simultaneously display output from multiple personal
computers (PCs).
Composite Device
(USB)
A peripheral device that supports more than one device class.
Computer Interface
The PSD’s physical receptacle or port for connecting to a
computer.
Connected Computer
A computing device connected to a PSD. May be a personal
computer, server, tablet, or any other computing device.
Connected Peripheral A Peripheral that is connected to a PSD.
Connection
A physical or logical conduit that enables Devices to interact
through respective interfaces. May consist of one or more
physical (e.g., a cable) or logical (e.g., a protocol) components.
Connector
The plug on a Connection that attaches to a Computer or
Peripheral Interface.
Device
An information technology product. In the context of this PP, a
Device is a PSD, a Connected Computer, or a Connected
Peripheral.
Digital Audio
Data stream that uses digital values to describe a sound wave in
sampled intervals.
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Display A device that visually outputs user data, such as a monitor.
Emulate Imitate the behavior of a device or a function in a device.
Endpoint (USB)
A source or a sink of data. Universal Serial Bus (USB) host is
centric; endpoints occur at the end of the communications
channel at the USB function.
Enumeration (USB)
A process that starts as soon as a device connects to the USB
host. In this process, the host and the device jointly define the
communications and power settings.
Extended Audio
Frequency Range
The range from 1Hz to 60 KHz
Fixed Device Filtration
(FDF)
PSD function that accepts or rejects peripheral devices based on
fixed parameters loaded during production.
Guard
A PSD function that requires multiple express user actions in
order to switch between Connected Computers using Connected
Peripherals.
Headphones
Computer audio peripheral device with one or more small
speakers
HID A device that allows input from, or sends output to human users.
Host (USB)
Initiates all communication on the USB and numbers the
connected devices.
Interface
A shared boundary across which two or more Devices exchange
information through a Connection.
Interface (USB)
Groups of endpoints. Each interface relates with a single device
function. An exception to this is endpoint zero, which is for
device configuration and not associated with any interface.
KM
A type of PSD that shares a keyboard and pointing device
between Connected Computers. A KM may optionally include an
analog audio device.
KVM
A type of PSD that shares a keyboard, video, and pointing device
between Connected Computers. A KVM may optionally include
an analog audio device and user authentication device.
Letter of Volatility
A letter issued by the manufacturer outlining whether onboard
memory can store data when the device is powered off (non-
volatile) or not (volatile).
Monitoring
The ability of a User to receive an indicator of the current Active
Interface.
Non-Selected
Computer
A Connected Computer that has no Active Interfaces with the
PSD.
Peripheral/Peripheral
Device
A Device with access that can be Shared or Filtered by a PSD.
Peripheral Interface
The PSD’s physical receptacle or port for connecting to a
Peripheral Device.
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Table 3 – ST Technical Definitions
1.5.2 Acronyms
Acronym Full Definition
ARC Audio Return Channel
Protocol
A set of rules or procedures for transmitting data between
electronic devices.
Remote Controller
Remote component of the PSD that extends the controls and
indications through a cable.
Secure State
An operating condition in which the PSD disables all connected
peripheral and connected computer interfaces when the
correctness of its functions cannot be ensured.
Selected Computer A Connected Computer that has Active Interfaces with the PSD.
Sub-Protocol A set of common commands flowing within a protocol.
Supported Peripheral A Peripheral Device that is technically supported by the PSD.
TOE Computer Video
Interface
TOE port used to connect the computer or other video source.
Touch Screen
A pointing device Peripheral Device that enable users to touch
one or more objects on the screen or to point the cursor device
to specific locations.
USB Audio codec
Computer audio peripheral device with USB digital
input/output, one or more analog audio outputs and one or
more analog audio inputs.
USB Device
USB devices are leafs in the USB tree that are connected to the
host.
USB Hub
A device that expands a single USB port into several so there are
more ports available to connect devices to a host system.
USB Type-C
Universal Serial Bus (USB) interface that supports DisplayPort
video output as an alternate mode.
User
A person that interacts with a PSD (or a process or mechanism
acting on behalf of a person).
User Data
Information that the User inputs to the Connected Computer or
is output to the User from the Connected Computer (and
including user authentication and credential information)
Video Data
Visual and audio information presented to the user through the
display device.
Video Wall
A tiled set of displays that allow the video output from a single
Selected Computer to be spanned across multiple individual
displays.
Whitelist
List containing one or more device attributes that will cause the
TOE to accept the devices having that attribute.
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CEC Consumer Electronics Control
dB Decibel
dBv A measurement of voltage ratio to 1 volt
DVI Digital Visual Interface (standard)
EDID Extended Display Identification Data
HDCP High-bandwidth Digital Content Protection
HDMI High-Definition Multimedia Interface (standard)
HEAC HDMI Ethernet and Audio Return Channel
HEC HDMI Ethernet Channel
HID Human Interface Device
HPD Hot Plug Detect
KHz Kilohertz
KM Keyboard, Mouse
KVM Keyboard, Video and Mouse
mV Millivolt
PC Personal Computer
PSD Peripheral Sharing Device
PS/2 Personal System/2
MCCS Monitor Command Control Set
OSP Organizational Security Policies
PSD Peripheral Sharing Device
SAR Security Assurance Requirement
SFR Security Functional Requirement
S/PDIF Sony/Philips Digital Interface Format
USB Universal Serial Bus
VGA Video Graphics Array (standard)
Table 4 – ST Acronyms
1.6 TOE Overview
1.6.1 TOE Architecture (High Level)
Sekuryx Secure Peripheral Sharing Devices (PSD) provide a secure medium to share a single set of
peripheral components such as keyboard, video display and mouse/pointing devices among one or
multiple computers over USB, and DisplayPort.
The Sekuryx Secure PSD product utilizes multiple isolated microcontrollers to emulate the connected
peripherals in order to prevent a multitude of threats. The TOE is also equipped with numerous uni-
directional data flows forcing devices to guarantee isolation of connected computer data channels.
Sekuryx Secure KVM port models:
• 2-Port
• 4-Port
• 8-Port
Sekuryx Secure KVM video outputs (displays):
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• Single head
• Dual-head
The Sekuryx Secure PSD is compatible with standard personal/portable computers, servers or thin-
clients. Connected computers are assumed to run off-the-shelf general-purpose operating systems
such as Windows or Linux. The PSD includes ports for the following interfaces, depending on model:
• USB keyboard – the TOE does not allow USB traffic to flow from the TOE to a connected
keyboard via the peripheral port
• USB mouse or other pointing device – the TOE does not allow USB traffic to flow from the TOE
to a connected pointing device via the peripheral port
• DisplayPort 1.2 Video Input (computer ports) – the TOE does not allow video traffic to flow
from the TOE to a connected computer via the computer port except for those sub-protocols
needed to establish initial connectivity between the computer and the peripheral monitor(s)
• DisplayPort 1.2 Video Output (peripheral port) – the TOE does not allow video traffic to flow
from a peripheral to the TOE via the peripheral port except for those sub-protocols needed to
establish initial connectivity between the computer and the peripheral monitor(s).
• 3.5mm Audio Input (computer ports) – the TOE does not allow audio output to flow from the
TOE to a connected computer via the computer ports (i.e. the use of a microphone peripheral
is not supported)
• 3.5mm Audio Output (peripheral port) – the TOE does not allow audio input to flow from a
peripheral to the TOE via the peripheral port (i.e. the use of a microphone peripheral is not
supported)
Tables 5, 6, and 7 below provide a summary of the Sekuryx Secure KVM security features by
supported interface types. A detailed description of the TOE security features and how they are
mapped to the claimed SFRs can be found in Section 6 (TOE Summary Specification) below.
1.6.2 TOE Details
1.6.2.1 Evaluated Products
# Model Name Description
Eval.
Version
1 CK4-P102 2-Port SH Secure DP KVM w/audio 4.30.001
2 CK4-P202 2-Port DH Secure DP KVM w/audio 4.30.001
Table 5 – Sekuryx 2-Port Secure TOE Identification
# Model Name Description
Eval.
Version
1 CK4-P104 4-Port SH Secure DP KVM w/audio 4.30.001
2 CK4-P204 4-Port DH Secure DP KVM w/audio 4.30.001
Table 6 – Sekuryx 4-Port Secure TOE Identification
# Model Name Description
Eval.
Version
1 CK4-P108 8-Port SH Secure DP KVM w/ audio 4.30.001
2 CK4-P208 8-Port DH Secure DP KVM w/ audio 4.30.001
Table 7 – Sekuryx 8-Port Secure TOE Identification
Notes:
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• DP = DisplayPort video.
• SH = Single head; DH = Dual head
• Description - Includes text that is printed on a label attached to each device on the bottom.
• Eval. Version – Firmware and hardware revision per each device.
• Sekuryx’s model name logic can be found in Appendix A.
1.6.2.2 Common Criteria Product Type
The TOE is classified as a “Peripheral Sharing Device” (KVM device) in the Common Criteria.
Hardware and firmware components are included in the TOE.
1.6.2.3 Peripheral Devices Supported by the TOE
The peripheral devices that supported by the TOE are listed in the following table.
Console Port Authorized Devices
Keyboard
Wired keyboard and keypad without internal USB hub or
composite device functions, unless the connected device has
at least one endpoint which is a keyboard or mouse HID class
Display
Display device (e.g. monitor, projector) that uses an interface
that is physically and logically compatible with the TOE ports
(DisplayPort)
Audio out Analog amplified speakers, Analog headphones
Mouse /
Pointing Device
Any wired mouse or trackball without internal USB hub or
composite device functions
Table 8 – Peripheral Devices supported by the TOE
1.6.2.4 Protocols Supported by the TOE
Tables 9, 10 and 11 below identify the console (peripheral) interface protocols supported by the TOE.
Tables 12, 13, and 14 below identify the host (computer) interface protocols supported by the TOE.
Model
CK4-P102
CK4-P202
Keyboard USB
1.1/2.0
✓ ✓
DP ✓ ✓
Mouse USB 1.1/2.0 ✓ ✓
Audio Analog
Stereo
✓ ✓
Table 9 – Console Port Protocols (2-Port TOE models)
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Model
CK4-P104
CK4-P204
Keyboard
USB 1.1/2.0
✓ ✓
DP ✓ ✓
Mouse USB
1.1/2.0
✓ ✓
Audio
Analog
Stereo
✓ ✓
Table 10 – Console Port Protocols (4-Port TOE models)
Model
CK4-P108
CK4-P208
Keyboard USB
1.1/2.0
✓ ✓
DP ✓ ✓
Mouse USB 1.1/2.0 ✓ ✓
Audio Analog Stereo
Output
✓ ✓
Table 11 – Console Port Protocols (8-Port TOE models)
Model
CK4-P102
CK4-P202
Keyboard USB
1.1/2.0
✓ ✓
DP ✓ ✓
Mouse USB 1.1/2.0 ✓ ✓
Audio Analog
Stereo
✓ ✓
Table 12 – Computer Port Protocols (2-Port TOE models)
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Model
CK4-P104
CK4-P204
Keyboard
USB 1.1/2.0
✓ ✓
DP ✓ ✓
Mouse USB
1.1/2.0
✓ ✓
Audio
Analog
Stereo
✓ ✓
Table 13 – Computer Port Protocols (4-Port TOE models)
Model
CK4-P108
CK4-P208
Keyboard USB
1.1/2.0
✓ ✓
DP ✓ ✓
Mouse USB 1.1/2.0 ✓ ✓
Audio Analog Stereo
Output
✓ ✓
Table 14 – Computer Port Protocols (8-Port TOE models)
1.6.2.5 Logical Scope of the TOE
1.6.2.5.1 Basic KVM TOE Function Overview
Secure KVM devices allow an individual user to utilize a set of peripherals to operate in an environment
with one or several isolated computers. KVM devices allow switching keyboard, mouse, display, and
audio from one isolated computer to another.
Table 15 below shows the various TOE services that were verified in the current evaluation.
TOE Service Verification
User peripheral isolation from source computer ✓
Admin access to management and log functions ✓
Restore factory defaults function ✓
Mapping user display to chosen computer ✓
Mapping user keyboard and mouse to chosen computer ✓
Mapping user audio device to chosen computer ✓
Table 15 – TOE Services
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1.6.2.6 Administrative configuration of the TOE
Table 16 below shows a summary of administrator administrative and security management features.
The authenticated Administrator is considered to be the administrator for the PSD PP. See section 6.2
for detailed description of the administration tool architecture.
Menu Option Administrator
Change Admin Access Credentials ✓
Dump Log ✓
Restore Factory Default
(reset)
✓
Terminate Session ✓
Table 16 – TOE Administrator Services and Accessibility
1.6.2.6.1 Change Admin Credentials option allows updating both the username and
password.
1.6.2.6.2 Dump Log (auditing) option allows generating a detailed report of security
functions such as self test, rejected peripheral USB device connection, restore
factory default (reset) and failure to log in.
1.6.2.6.3 Restore Factory Default (reset) option causes the following to occur:
1. Administrator log-in credential will be reset back to default.
2. The TOE will perform power down for 1,000ms followed by power up.
3. During power down, all connected devices will be disconnected from the computers and all
internal cache other than auditing log will be wiped.
4. After power up the TOE buzzer will buzz twice to indicate completion of power reset and
successful self test results.
1.6.2.6.4 Terminate Session logs out the authenticated Administrator.
1.6.2.7 TOE Security Functions Overview
The following list is an overview of the security features supported by the TOE.
TOE Keyboard and Mouse Security Functions
1. No data is stored in non-volatile memory (SRAM only).
2. USB Keyboard and mouse data flows are converted to a serial data flow channel which is
isolated from each connected computer and all TOE internal circuitry.
3. Keyboard and mouse channels are isolated electrically and logically from each connected
computer and all TOE internal circuitry.
4. Uni-directional data flow enforced by using uni-directional optical data diodes.
5. Temporary power shut down during channel switching to eliminate previous cached
keyboard/mouse commands.
6. Device/Host emulators used to prevent connected computer and peripheral device direct
communication/data leakage.
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7. Device/Host emulators used to maintain KM emulation system on all channels during TOE
operation (enabling non-selected connected computers to have emulation even when the user
uses another PC).
8. The TOE rejects all unauthorized peripheral devices.
9. Keyboard LEDs will not turn on despite valid keyboard commands being executed (ex: Caps
Lock LED will not turn on) to enforce unidirectional communication.
10. The TOE only allows valid and simple keyboard and mouse commands. All other USB traffic is
rejected. All advanced keyboard and mouse devices will have their non-basic features disabled
by the TOE.
11. Keyboard and mouse channels remain isolated when the TOE is not powered.
TOE External Interfaces Security Functions
1. No docking protocols supported by the TOE.
2. No analog audio input allowed by peripherals connected to the TOE.
3. Devices allowed by the TOE:
• Wired USB 1.1/2.0 keyboard and mouse
• 3.5mm Analog audio output jack
• DP 1.2 input/DP 1.2 output
TOE Audio Subsystem Security Functions
1. Stereo audio channel for each connected computer that is isolated electronically/logically
from all TOE internal circuitry.
2. No analog microphones allowed by the TOE.
3. LM4880 Boomer audio power amplifier designed specifically to provide high quality output
power with a minimal amount of external components using surface mount packaging.
4. LM4880 Boomer analog output amplifier enforces uni-directional data flow from computer to
TOE on both left and right stereo audio with internal transistors to prevent microphone access
to the computer.
5. Audio data flow is not converted, stored, or used by the TOE to prevent data leakage.
6. Audio channels remain isolated when the TOE is not powered.
TOE Video Subsystem Security Functions
1. Video channels are isolated, disabling bidirectional communication with monitors/displays
using dedicated EEPROMs for EDID emulation. The video output signal will be transmitted to
the display using a single dedicated EDID address, preventing any unauthorized transactions
between the display and the PC.
2. Video channels remain isolated when the TOE is not powered.
3. Uni-directional EDID read/write process prevents bi-directional communication.
4. TOE rejects all invalid EDID devices.
5. DP 1.2 video inputs supported by the TOE.
TOE User Control and Monitoring Security Functions
1. Visual indications of current channel state via TOE push-button LEDs.
2. Connected computer channel can be changed by manual pressing of push-button on TOE.
3. Front panel LED indications cannot be dimmed or altered in any way during TOE operation.
Self-Testing
1. TOE self-testing function that forcibly executes prior to system power up.
2. Self-testing function failure temporarily disables normal TOE operation until system reboot
and subsequent passing of all self-test functions.
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3. Self-testing function failure has visual and audible indications (flashing push-button LEDs,
pulsing relays).
Anti-Tampering
1. Permanently active anti-tampering system powered by external supply or internal backup
battery (rated for 10 years of operation).
2. Anti-tampering system trigger forces isolation of all connected computers and peripheral
devices.
3. Visible and audible indications occur after anti-tampering system trigger (flashing push-
button LEDs, pulsing relays, internal alarm beeping).
4. Generated log function to provide an auditable trail for TOE security events.
5. All TOE microcontrollers are protected against firmware read/write from external tools.
6. Uniquely numbered holographic tamper evident label (TEL) placed on TOE to indicate any
physical attempt to access TOE internal circuitry.
A more detailed version of this overview is provided in Section 6 below.
1.7 TOE Scope and Boundary
1.7.1 Overview
The TOE is a Peripheral Sharing Device that supports the following types of peripherals:
- Analog audio output
- Keyboard/Mouse input
- Video output
The physical boundary of the TOE consists of (refer to Figure 1, Figure 2, and Table 17 below):
No. Physical Boundary of TOE
1 One Sekuryx Secure KVM Switch
2 The TOE computer interface cables that are shipped with the product
3
The permanently programmed embedded firmware inside the TOE on each
microcontroller and processor
4 Log data, settings data, state data stored in the TOE
5 The TOE power supply that is shipped with the product
6
User Guidance Manual. Current version available for download at:
https://sekuryx.com/documents-niap4/
7
Administrator Guidance. Current version available for download at:
https://sekuryx.com/documents-niap4/
Table 17 – TOE Physical Boundary Composition
The evaluated TOE configuration only includes supplied computer interface cables attached to the TOE
(no peripherals are supplied by Sekuryx). The following figures represent the TOE and its
environment.
Note: Some TOE models support the operation of multiple user displays. Specifically, the model names
that include “2” after “CK4-P” support the connection of up to two displays to the console ports. This
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allows for switching of computers that have multi-monitor display capabilities. Models that do not use
this notation in the model name are single head for switchable video output.
The figures below show representative examples of supported TOE models and their connections to
peripherals and computers. This includes 2-port and 4-port models. 8-port models behave the same
way as 2-port and 4-port models except that additional connected computers are supported.
Figure 1: Standard Setup of 2-Port KVM TOE Installation
Figure 2: Standard Setup of 4-Port TOE installation
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1.7.2 Environment
The following tables identify hardware components and indicate whether or not each component is in
the TOE or Environment.
Component
Part Number
(P/N)
Description
Each device listed in
Tables 5, 6, and 7 above.
Same as model
number
TOE Hardware
Sekuryx KVM Cables
CB-5021
KVM/KM Cable (1.8 m), USB Type-A to USB Type-
B*
CB-5022 KVM/KM Cable (1.8 m), Audio out, 3.5mm*
CB-5050 KVM Cable (1.8 m), DP to DP, USB A to USB B*
Table 18 – TOE Components
*These cables are used for connecting the TOE to peripheral devices/connected computers.
Component Description
Standard USB Mouse Shared Peripheral Hardware
Standard USB Keyboard Shared Peripheral Hardware
Standard Computer Display(s) Shared Peripheral Hardware
Audio Device (Speakers: supports 3.5mm
connector)
Shared Peripheral Hardware
Standard PC, Server, portable computer or thin
client running any operating system
Connected Computer(s)
Table 19 – Environment Components
1.8 Guidance Documents
User manuals for each TOE model and an administrative guide are available for download via the
following link: https://sekuryx.com/documents-niap4/. The following documents on the page are
relevant to the TOE:
• Sekuryx Secure KVM Administration and Security Management Tool Guide (Non-CAC), Version
1.0, April 6, 2021
• User Manual Sekuryx Secure DP KVM Switch with CAC Port and 4K Ultra-HD Support, Revision
1.0, July 21, 2021
Note that the User Manual references both “CAC” and “Non-CAC” models. For this evaluation, Non-
CAC models should be referenced, and so all discussion in the referenced document applies to the
TOE except for that relating to the physical CAC port and its logical operation.
1.9 Features Outside of TOE Evaluation Scope
This section identifies any items that are specifically excluded from the TOE.
There are no items excluded from the TOE.
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2 Security Problem Description
This section lists the assumptions pertaining to the environment in which the TOE is to be used in
and describes the conditions for the secure operation of the TOE.
Note: The following content in this section has been taken from the Security Problem Description of
the claimed PSD PP and the other PP-Modules in the claimed PP-Configuration and are replicated
here for clarity.
2.1 Assumptions
The following table defines the assumptions regarding the deployment and use of the TOE. These
assumptions are defined in the PSD PP and the PP-Modules that comprise the PP-Configuration that
the TOE claims conformance to.
Assumption Definition
Protection Profile for Peripheral Sharing Device
A.NO_TEMPEST
Computers and peripheral devices connected to the PSD are not
TEMPEST approved.
(Added from PP-Module for Keyboard/Mouse Devices) 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
will 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.
PP-Module for Analog Audio Output Devices
A.NO_MICROPHONES
Users are trained not to connect a microphone to the TOE audio
output interface.
PP-Module for Keyboard/Mouse Devices
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N/A – this PP-Module does not define any assumptions beyond those defined in the PSD PP.
PP-Module for Video/Display Devices
A.NO_SPECIAL_ANALOG_CA
PABILITIES
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 20 – Assumptions
2.2 Organizational Security Policies
No Organizational Security Policies (OSPs) are listed in the claimed PP that needs to be addressed
by the TOE.
2.3 Threats
The following table defines the threats expected to be mitigated by the TOE. These threats are defined
in the PSD PP and the PP-Modules that comprise the PP-Configuration that the TOE claims
conformance to.
Threat Definition
Protection Profile for Peripheral Sharing Device
T.DATA_LEAK
A connection via the PSD 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.
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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.
T.FAILED
Detectable failure of a PSD may cause an unauthorized
information flow or weakening of PSD security functions.
PP-Module for Analog Audio Output Devices
T.MICROPHONE_USE
A malicious agent could use an unauthorized peripheral device
such as a microphone, connected to the TOE audio out peripheral
device interface to eavesdrop or transfer data across an air‐gap
through audio signaling.
T.AUDIO_REVERSED
A malicious agent could repurpose an authorized audio output
peripheral device by converting it to a low‐gain microphone to
eavesdrop on the surrounding audio or transfer data across an
air‐gap through audio signaling.
PP-Module for Keyboard/Mouse Devices
N/A – this PP-Module does not define any threats beyond those defined in the PSD PP.
PP-Module for Video/Display Devices
N/A – this PP-Module does not define any threats beyond those defined in the PSD PP.
Table 21 – Threats
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3 Security Objectives
This chapter defines the security objectives for the TOE and the Operational Environment.
• Security Objectives for TOE are directly addressed by TOE
• Security Objectives for Operational environment are not addressed directly by TOE. These
security objectives are addressed by non-technical methods, such as through the IT domain.
3.1 Security Objectives for the TOE
The following table defines the security objectives that must be satisfied by the TOE. These objectives
are defined in the PSD PP and the PP-Modules that comprise the PP-Configuration that the TOE claims
conformance to.
Security Objective Definition
Protection Profile for Peripheral Sharing Device
O.COMPUTER_INTERFACE_I
SOLATION
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.
O.COMPUTER_INTERFACE_I
SOLATION_TOE_UNPOWER
ED
The PSD shall not allow data to transit a PSD‐Computer interface
while the PSD is unpowered.
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.
O.NO_USER_DATA_RETENTI
ON
The PSD shall not retain user data in non‐volatile memory after
power up or, if supported, factory reset.
O.NO_OTHER_EXTERNAL_IN
TERFACES
The PSD shall not have any external interfaces other than those
implemented by the TSF.
O.LEAK_PREVENTION_SWIT
CHING
The PSD shall ensure that there are no switching mechanisms that
allow signal data leakage between connected computers.
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.
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A conformant TOE may also provide a management function to
configure some aspects of the TSF. If the TOE provides this
functionality, it shall ensure that whatever management functions
it provides can only be performed by authorized administrators
and that an audit trail of management activities is generated.
O.PERIPHERAL_PORTS_ISOL
ATION
The PSD shall ensure that data does not flow between peripheral
devices connected to different PSD interfaces.
O.REJECT_UNAUTHORIZED_
PERIPHERAL
The PSD shall reject unauthorized peripheral device types and
protocols.
O.REJECT_UNAUTHORIZED_
ENDPOINTS
The PSD shall reject unauthorized peripheral devices connected
via a Universal Serial Bus (USB) hub.
O.NO_TOE_ACCESS
The PSD firmware, software, and memory shall not be accessible
via its external ports.
O.TAMPER_EVIDENT_LABE
L
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.
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.
O.SELF_TEST
The PSD shall perform self‐tests following power up or powered
reset.
O.SELF_TEST_FAIL_TOE_DIS
ABLE
The PSD shall enter a secure state upon detection of a critical
failure.
O.SELF_TEST_FAIL_INDICAT
ION
The PSD shall provide clear and visible user indications in the
case of a self‐test failure.
PP-Module for Analog Audio Output Devices
O.UNIDIRECTIONAL_AUDIO
_OUT
The PSD shall enforce the unidirectional flow of audio data from
the analog audio computer interface to the analog audio
peripheral interface.
O.COMPUTER_TO_AUDIO_IS
OLATION
The PSD shall isolate the analog audio output function from all
other TOE functions.
PP-Module for Keyboard/Mouse Devices
O.EMULATED_INPUT
The TOE shall emulate the keyboard and/or mouse functions
from the TOE to the connected computer.
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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.
PP-Module for Video/Display Devices
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.
O.UNIDIRECTIONAL_VIDEO
The TOE shall enforce unidirectional video data flow from the
connected computer video interface to the display interface only.
Table 22 – Security Objectives for the TOE
3.2 Security Objectives for the Operational Environment
The following table defines the security objectives that must be satisfied by the TOE’s operational
environment to ensure that the TOE’s functions will be sufficient to mitigate the defined threats.
These objectives are defined in the PSD PP and the PP-Modules that comprise the PP-Configuration
that the TOE claims conformance to.
Security Objective Definition
Protection Profile for Peripheral Sharing Device
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.
PP-Module for Analog Audio Output Devices
OE.NO_MICROPHONES
The operational environment is expected to ensure that
microphones are not plugged into the TOE audio output
interfaces.
PP-Module for Keyboard/Mouse Devices
N/A – this PP-Module does not define any environmental security objectives beyond those
defined in the PSD PP.
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PP-Module for Video/Display Devices
OE.NO_SPECIAL_ANALOG_C
APABILITIES
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 23 – Security Objectives for the Operational Environment
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4 Security Requirements
The following section describes the IT security requirements of the TOE and its operational
environment. The Common Criteria separates the TOE security requirements into two distinct
categories:
1. Security functional requirements (SFRs) the TOE needs to satisfy to pass the security
objectives (examples are listed below).
• Identification/Authentication
• Security management
• User information protection
2. Security assurance requirements (SARs) specify evidence that provides grounds for
confidence the TOE in its operational environment can satisfy the security objectives
(examples are listed below).
• Testing
• Configuration Management
• Vulnerability Assessment
The SFRs and SARs are discussed in more detail in the following subsections.
4.1 TOE Security Functional Requirements
The SFRs the TOE will satisfy are listed below in this section.
4.1.1 Overview
The TOE claims all of the mandatory SFRs defined in the PP and PP-Modules that belong to the
claimed PP-Configuration. The TOE also meets some of the optional and selection-based SFRs in the
PP and PP-Modules. For Base-PP SFRs that are modified by one or more of the claimed PP-Modules,
the modifications as required by those PP-Modules have been made.
The SFRs have been replicated below for clarity. Table 24 below displays the SFR IDs, their names,
and where they originate from.
SFR ID Name Source
FAU_GEN.1 Audit Data Generation PSD PP (optional)
FDP_AFL_EXT.1 Audio Filtration Audio Output Module (mandatory)
FDP_APC_EXT.1
Active PSD Connections PSD PP (mandatory)
Note that the ST iterates this SFR for each of the claimed PP-Modules, per
the instructions found in section 5.1.2 of each PP-Module.
FDP_CDS_EXT.1
Connected Displays
Supported
Video/Display Module (selection-based)
FDP_FIL_EXT.1/KM
Device Filtering
(Keyboard/Mouse)
Keyboard/Mouse Module (optional)
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FDP_IPC_EXT.1 Internal Protocol Conversion Video/Display Module (selection-based)
FDP_PDC_EXT.1
Peripheral Device
Connection
PSD PP (mandatory)
FDP_PDC_EXT.2/AO
Peripheral Device
Connection (Audio Output)
Audio Output Module (mandatory)
FDP_PDC_EXT.2/KM
Authorized Devices
(Keyboard/Mouse)
Keyboard/Mouse Module (mandatory)
FDP_PDC_EXT.2/VI
Peripheral Device
Connection (Video Output)
Video/Display Module (mandatory)
FDP_PDC_EXT.3/KM
Authorized Connection
Protocols (Keyboard/Mouse)
Keyboard/Mouse Module (mandatory)
FDP_PDC_EXT.3/VI
Authorized Connection
Protocols (Video Output)
Video/Display Module (mandatory)
FDP_PUD_EXT.1
Powering Unauthorized
Devices
Audio Output Module (mandatory)
FDP_RIP.1/KM
Residual Information
Protection (Keyboard Data)
Keyboard/Mouse Module (selection-
based)
FDP_RIP_EXT.1
Residual Information
Protection
PSD PP (mandatory)
FDP_RIP_EXT.2
Purge of Residual
Information
PSD PP (optional)
FDP_SPR_EXT.1/DP
Sub-Protocol Rules
(DisplayPort Protocol)
Video/Display Module (selection-based)
FDP_SWI_EXT.1 PSD Switching PSD PP (mandatory)
FDP_SWI_EXT.2 PSD Switching Methods PSD PP (selection-based)
FDP_SWI_EXT.3 Tied Switching
Keyboard/Mouse Module (selection-
based)
FDP_UDF_EXT.1/AO
Unidirectional Data Flow
(Audio Output)
Audio Output Module (mandatory)
FDP_UDF_EXT.1/KM
Unidirectional Data Flow
(Keyboard/Mouse)
Keyboard/Mouse Module (mandatory)
FDP_UDF_EXT.1/VI
Unidirectional Data Flow
(Video Output)
Video/Display Module (mandatory)
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FIA_UAU.2
User Authentication Before
Any Action
PSD PP (optional)
FIA_UID.2
User Identification Before
Any Action
PSD PP (optional)
FMT_MOF.1
Management of Security
Functions Behavior
PSD PP (optional)
FMT_SMF.1
Specification of Management
Functions
PSD PP (optional)
FMT_SMR.1 Security Roles PSD PP (optional)
FPT_FLS_EXT.1
Failure with Preservation of
Secure State
PSD PP (mandatory)
FPT_NTA_EXT.1 No Access to TOE PSD PP (mandatory)
FPT_PHP.1
Passive Detection of Physical
Attack
PSD PP (mandatory)
FPT_PHP.3 Resistance to Physical Attack PSD PP (optional)
FPT_STM.1 Reliable Time Stamps PSD PP (optional)
FPT_TST.1 TSF Testing PSD PP (mandatory)
FPT_TST_EXT.1 TSF Testing PSD PP (mandatory)
FTA_CIN_EXT.1 Continuous Indications PSD PP (selection-based)
Table 24 – TOE SFR Overview
4.1.2 Class FAU: Security Audit
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, [all administrative
functions claimed in FMT_MOF.1 and FMT_SMF.1]].
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
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b. For each audit event type, based on the auditable event definitions
of the functional components included in the PP/ST, [no other
information].
4.1.3 Class FDP: User Data Protection
FDP_AFL_EXT.1 Audio Filtration
FDP_AFL_EXT.1.1 The TSF shall ensure outgoing audio signals are filtered as per [Audio
Filtration Specifications table].
Frequency
(kHz)
Minimum Attenuation
(dB)
Maximum Voltage After
Attenuation
14 23.9 127.65 mV
15 26.4 95.73 mV
16 30.8 57.68 mV
17 35.0 35.57 mV
18 38.8 22.96 mV
19 43.0 14.15 mV
20 46.0 10.02 mV
30 71.4 0.53 mV
40 71.4 0.53 mV
50 71.4 0.53 mV
60 71.4 0.53 mV
Table 25 – Audio Filtration Specifications
FDP_APC_EXT.1/AO Active PSD Connections (Audio Output)
FDP_APC_EXT.1.1/AO The TSF shall route user data only from the interfaces selected by the user.
FDP_APC_EXT.1.2/AO 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/AO The TSF shall ensure that no data transits the TOE when the TOE is
powered off.
FDP_APC_EXT.1.4/AO The TSF shall ensure that no data transits the TOE when the TOE is in a
failure state.
Application Note: This SFR is originally defined in the Base-PP but is refined and iterated to
apply to the audio output interface per section 5.1.2 of the Audio Output PP-
Module.
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FDP_APC_EXT.1/KM Active PSD Connections (Keyboard/Mouse)
FDP_APC_EXT.1.1/KM The TSF shall route user data only to 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.
Application Note: This SFR is originally defined in the Base-PP but is refined and iterated to
apply to the audio output interface per section 5.1.2 of the Keyboard/Mouse PP-
Module.
FDP_APC_EXT.1/VI Active PSD Connections (Video/Display)
FDP_APC_EXT.1.1/VI The TSF shall route user data only from the interfaces selected by the user.
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.
Application Note: This SFR is originally defined in the Base-PP but is refined and iterated to
apply to the audio output interface per section 5.1.2 of the Video/Display PP-
Module.
FDP_CDS_EXT.1 Connected Displays Supported
FDP_CDS_EXT.1.1 The TSF shall support [one connected display for TOE models with CK4-
10X model names, multiple connected displays for all other TOE models]
at a time.
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.
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Application Note: The TSF enforces fixed device filtration on the keyboard/mouse interface by
implicitly blacklisting all USB devices that are not keyboard or mouse
devices.
FDP_IPC_EXT.1 Internal Protocol Conversion1
FDP_IPC_EXT.1.1 The TSF shall convert the [DisplayPort] protocol at the [DisplayPort
computer video interface] into the [HDMI] protocol within the TOE.
FDP_IPC_EXT.1.2 The TSF shall output the [HDMI] protocol from inside the TOE to [peripheral
display interface(s)] as [[DisplayPort] protocol].
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.
FDP_PDC_EXT.2/AO Peripheral Device Connection (Audio Output)
FDP_PDC_EXT.2.1/AO The TSF shall allow connections with authorized devices as defined in
[Appendix E of the Analog Audio Output Devices Module] and [
• authorized devices and functions as defined in the PP-Module for
Keyboard/Mouse Devices,
• 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.
FDP_PDC_EXT.2.2/AO The TSF shall allow connections with authorized devices presenting
authorized interface protocols as defined in [Appendix E of the Analog Audio
Output Devices Module] and [
• authorized devices presenting authorized interface protocols as
defined in the PP-Module for Keyboard/Mouse Devices,
1
As modified by NIAP TD0586
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• 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.
FDP_PDC_EXT.2/KM Peripheral Device Connection (Keyboard/Mouse)
FDP_PDC_EXT.2.1/KM The TSF shall allow connections with authorized devices and functions as
defined in [Appendix E of the Keyboard/Mouse Devices Module] and [
• authorized devices as defined in the PP-Module for Audio Output
Devices,
• 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.
FDP_PDC_EXT.2.2/KM The TSF shall allow connections with authorized devices presenting
authorized interface protocols as defined in [Appendix E of the
Keyboard/Mouse Devices Module] and [
• authorized devices presenting authorized interface protocols as
defined in the PP-Module for Audio Output Devices,
• 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.
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 of the Video/Display Devices Module] and [
• authorized devices as defined in the PP-Module for Audio Output
Devices,
• 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 of the
Video/Display Devices Module] and [
• authorized devices presenting authorized interface protocols as
defined in the PP-Module for Audio Output Devices,
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• 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.
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].
FDP_PDC_EXT.3/VI Authorized Connection Protocols (Video Output)
FDP_PDC_EXT.3.1/VI The TSF shall have interfaces for the [DisplayPort] 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].
FDP_PUD_EXT.1 Powering Unauthorized Devices
FDP_PUD_EXT.1.1 The TSF shall not provide power to any unauthorized device connected to
the analog audio peripheral interface.
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.
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.
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.
FDP_SPR_EXT.1/DP Sub-Protocol Rules (DisplayPort Protocol)
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FDP_SPR_EXT.1.1/DP The TSF shall apply the following rules for the [DisplayPort] protocol:
• block the following video/display sub-protocols:
o [CEC,
o EDID from computer to display,
o HDCP,
o MCCS]
• allow the following video/display sub-protocols:
o [EDID from display to computer,
o HPD from display to computer,
o Link Training].
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].
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.
FDP_SWI_EXT.2.2 The TSF shall ensure that switching can be initiated only through express
user action using [console buttons].
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.
FDP_UDF_EXT.1/AO Unidirectional Data Flow (Audio Output)
FDP_UDF_EXT.1.1/AO The TSF shall ensure [analog audio output data] transits the TOE
unidirectionally from [the TOE analog audio output computer] interface
to [the TOE analog audio output peripheral] interface.
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.
FDP_UDF_EXT.1/VI Unidirectional Data Flow (Video Output)
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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.
4.1.4 Class FIA: Identification and Authentication
FIA_UAU.2 User Identification 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.
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.
4.1.5 Class FMT: Security Management
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
[administrator authentication, dump log, restore factory default, terminate
session] to [the authorized administrators].
FMT_SMF.1 Specification of Management Functions
FMT_SMF.1.1 The TOE shall be capable of performing the following management
functions: [change administrator access credential, dump log, restore
factory default, terminate session].
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.
4.1.6 Class FPT: Protection of the TSF
FPT_FLS_EXT.1 Failure with Preservation of Secure State
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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 anti-tamper
function].
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].
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.
FPT_PHP.3 Resistance to Physical Attack2
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.
Application Note: This SFR is modified per NIAP TD0583 to include reference to remote
controllers. This modification is not applicable to the TOE because it does
not have any remote controllers.
FPT_STM.1 Reliable Time Stamps
FPT_STM.1.1 The TSF shall be able to provide reliable time stamps.
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 [upon reset button activation]] to demonstrate the correct
operation of [user control functions and [active anti-tamper functionality]].
FPT_TST.1.2 The TSF shall provide authorized users with the capability to verify the
integrity of [TSF data].
2
As modified by NIAP TD0583
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FPT_TST.1.3 The TSF shall provide authorized users with the capability to verify the
integrity of the [TSF].
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] indication of failure and by shutdown of normal TSF functions.
4.1.7 Class FTA: TOE Access
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: a panel with lights.
Application Note: The selected computer is indicated with a panel with lights that
corresponds to the computer selection 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].
4.2 Rationale for TOE Security Requirement Dependencies
The TOE claims all SFRs from the claimed PP and all claimed PP-Modules with the following
exceptions:
- FDP_RDR_EXT.1 (from Keyboard/Mouse Module) – this is an optional SFR that the TSF does
not claim to address.
- FDP_SPR_EXT.1/DVI-D (from Video/Display Devices Module) – this is a selection-based SFR
that is only claimed if “DVI-D” is selected in FDP_PDC_EXT.3.1/VI. Because this selection is
not made, the SFR is appropriately omitted.
- FDP_SPR_EXT.1/DVI-I (from Video/Display Devices Module) – this is a selection-based SFR
that is only claimed if “DVI-I” is selected in FDP_PDC_EXT.3.1/VI. Because this selection is
not made, the SFR is appropriately omitted.
- FDP_SPR_EXT.1/HDMI (from Video/Display Devices Module) – this is a selection-based SFR
that is only claimed if “HDMI” is selected in FDP_PDC_EXT.3.1/VI. Because this selection is
not made, the SFR is appropriately omitted.
- FDP_SPR_EXT.1/USB (from Video/Display Devices Module) – this is a selection-based SFR
that is only claimed if “USB Type-C with DisplayPort as alternate function” is selected in
FDP_PDC_EXT.3.1/VI. Because this selection is not made, the SFR is appropriately omitted.
- FDP_SPR_EXT.1/VGA (from Video/Display Devices Module) – this is a selection-based SFR
that is only claimed if “VGA” is selected in FDP_PDC_EXT.3.1/VI. Because this selection is not
made, the SFR is appropriately omitted.
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In all cases, the omitted SFRs have been excluded from the TSF because they refer to conditional
functionality where the TOE did not satisfy the required condition or to optional functionality that
may be excluded at the TOE developer’s discretion.
4.3 TOE Security Assurance Requirements
The table below defines the SARs claimed by the TOE. These are the same SARs that are required by
the claimed PP-Configuration.
Assurance Class
Assurance
Component
ID
Assurance Components Description
Development ADV_FSP.1 Basic Functional Specification
Guidance Documents
AGD_OPE.1 Operational User Guidance
AGD_PRE.1 Preparative Procedures
Life Cycle Support
ALC_CMC.1 Labeling of the TOE
ALC_CMS.1 TOE CM coverage
Tests ATE_IND.1 Independent Testing – Conformance
Vulnerability
Assessment
AVA_VAN.1 Vulnerability Survey
Table 26 – TOE Security Assurance Requirements
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5 Conformance Claims
The following section describes the ST Conformance Claims.
5.1 CC Conformance Claims
This ST is compliant with the following CC documents:
• [CC1] - Common Criteria for Information Technology Security Evaluation, Part 1:
Introduction and General Model, CCMB-2012-09-001, Version 3.1 Revision 5, April 2017.
• [CC2] - Common Criteria for Information Technology Security Evaluation, Part 2: Security
Functional Components, CCMB-2012-09-002, Version 3.1 Revision 5, April 2017.
• [CC3] - Common Criteria for Information Technology Security Evaluation, Part 3: Security
Assurance Components, CCMB-2012-09-003, Version 3.1 Revision 5, April 2017.
• [CEM] - Common Methodology for Information Technology Security Evaluation, Evaluation
Methodology, CCMB-2012-09-004, Version 3.1, Revision 5, April 2017.
• [Addenda] - CC and CEM addenda – Exact Conformance, Selection-Based SFRs, Optional
SFRs, Version 0.5, May 2017.
This ST is CC Part 2 extended and CC Part 3 conformant.
5.2 PP Conformance Claims
This ST claims exact conformance to the PP‐Configuration for Peripheral Sharing Device, Analog
Audio Output Devices, Keyboard/Mouse Devices, and Video/Display Devices, Version 1.0 and the
following technical decisions:
1. TD0506 - Missing Steps to disconnect and reconnect display, published date 02/28/2020
2. TD0507 - Clarification on USB plug type, published date 03/03/2020
3. TD0514 - Correction to MOD_VI FDP_APC_EXT.1 Test 3 Step 6, published date 05/18/2020
4. TD0518 - Typographical error in Dependency Table, published date 06/15/2020
5. TD0539 - Incorrect selection trigger in FTA_CIN_EXT.1 in MOD_VI_V1.0, published date
07/11/2020
6. TD0557 - Correction to Audio Filtration Specification Table in FDP_AFL_EXT.1, published
date 12/08/2020
7. TD0583 – FPT_PHP.3 modified for PSD remote controllers, published date 05/12/2021
8. TD0584 - Update to FDP APC_EXT.1 Video Tests, published date 04/29/2021
9. TD0585 - Update to FDP_APC_EXT.1 Audio Output Tests, published date 04/29/2021
10. TD0586 - DisplayPort and HDMI Interfaces in FDP_IPC_EXT.1, published date 05/11/2021
11. TD0593 - Equivalency Arguments for PSD, published date 06/03/2021
5.3 ST Conformance Requirements
This Security Target is in exact conformance with the PP. That is, the ST meets all the assurance
requirements as defined by section D.2 of CC Part 1.
The mandatory requirements of the PP and all PP-Modules contained within the PP-Configuration
are met. The ST is an instantiation of the claimed PP-Configuration. Additionally, optional
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requirements from these materials are claimed as needed and selection-based requirements are
claimed where required. The ST does not omit any mandatory requirements, nor does it define or
claim any requirements that are not defined in any of the components of the claimed PP-
Configuration.
This ST meets all assurance requirements defined in the PP-Configuration.
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6 TOE Summary Specification
This section summarizes the security functions of the TOE and the subsequent Assurance Measures
taken to ensure their proper implementation. See Table 24 in Section 4 for the entire list of SFRs
that address the security objectives for this TOE. These objectives will be broken down in the
subsequent sections for further detail.
6.1 TOE External Interfaces Security Functions
[O.NO_OTHER_EXTERNAL_INTERFACES]: FDP_PDC_EXT.1
[O.REJECT_UNAUTHORIZED_PERIPHERAL]: FDP_PDC_EXT.1
[O.REJECT_UNAUTHORIZED_ENDPOINTS]: FDP_PDC_EXT.1
The TOE only supports AC/DC power, USB keyboard and mouse, KVM video (DP 1.2 in/DP 1.2 out),
and analog audio output devices. All other peripheral types are rejected, either physically (because
the TOE does not support the required physical interface) or logically (because the TOE does not
recognize the connected peripheral as authorized).
6.2 TOE Administration, User Control, and Monitoring Security Functions
[O.AUTHORIZED_USAGE]: 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
Each TOE is equipped with Administration and Security Management Tool that can be initiated by
running an executable file on a computer with keyboard connected to the same computer via the
TOE. The tool requires administrator to be successfully identified and authenticated by name and
password in order to gain access to any supported feature. The TOE has a menu-driven interface in
which the administrator can initiate the supported functions. See below for descriptions of the
supported features.
• Change Admin Access Credentials
o Updates the username and password for the “admin” account
• Dump Log
o Prints out the last 100 logs the TOE recorded
• Restore Factory Default
o Resets the administrator credentials to default settings
• Terminate Session
o Ends the current administrative tool session
The TOE is shipped with default credentials for the administrator account; these should be changed
on first use as part of the initial setup process. Successful and failed authentication attempts are
logged, as are logouts. The TOE does not enforce any failure limitations (e.g. lockout after a certain
number of successive failures). If an administrator has lost their username and/or password, they
must contact the manufacturer for assistance.
The administrator account passwords as well as the name of the account itself can both be changed.
The restrictions for each are as follows:
• Minimum 4 characters
• Maximum 8 characters
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• All Letters (Upper and Lower case), Numbers, and the following special characters are
allowed ! @ # $ % ^ & * ( ) _ + - = “ ? /
• The following special characters are not allowed ~ ` { } | [ ] \ : ; ‘ < > , .
• Any other character not specified above is not allowed.
• Space and Tab are not allowed
All usage of the TOE requires authentication to the Administration and Security Management Tool
except for switching. All TOE models can be switched using push-buttons on the TOE chassis.
There are no switching mechanisms that can be engaged using automatic port scanning, control
through a connected computer, or control through keyboard shortcuts. The console buttons are the
only available switching mechanisms.
The TOE has a non-volatile memory event log which records all abnormal security events that occur
within TOE operation. This log can be accessed by the identified and authorized administrator and
dumped into a .txt file using a connected computer and a program. If the TOE anti-tampering state
has been triggered, the access log can only be accessed by de-soldering the memory IC from the
internal circuitry and extracted using low-level factory tools (TOE is permanently disabled).
The following events are logged in sequential order with time/date stamp and Pass/Fail status:
APU Administrator Credential Update
ALO Administrator Log On
ALF Administrator Log Off
ARM Arming A/T System
EDL EDID Learn
LGD LOG Dump
PWU Power Up
PWD Power Down
AFD Restore Factory Default
RKM Rejected Keyboard or Mouse
STS Self-Test
TMP Device Tampered, Review by MFR only
The TOE can store up to 100 events. When the allocated memory is fully used, new events will be
recorded over the oldest events (first in first out mode).
The TOE includes an internal system clock function that is used for time stamps of audit records.
For non-isolator TOE models, the TOE indicates the selected channel using a panel of LEDs that are
located directly above the channel selection buttons for the connected computer. When the user
presses a channel selection button, the corresponding LED will light up to indicate the selected
computer. The channel selection buttons are also backlit. During operation, all front panel LED
indications cannot be turned off or dimmed by the user in any way including after Restore Factory
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Default (reset). This prevents user confusion of current TOE state.3 When the TOE has booted
successfully, it will default to computer 1 being the selected computer.
[O.LEAK_PREVENTION_SWITCHING]: FDP_SWI_EXT.1, FDP_SWI_EXT.2
All switching mechanisms must be deliberately engaged by the user. There are no mechanisms that
allow data intended for the selected computer to be transmitted to a different computer, and there
are no interfaces that allow data to be transmitted directly between computers.
6.3 TOE Tampering Protection
In order to mitigate potential tampering and replacement, the TOE is devised to ensure that any
replacement may be detected, any physical modification is evident, and any logical modification may
be prevented. The tamper protection mechanism is only triggered by tamper detection or failure of
self-testing; there is no method by which a user can falsely or accidentally trigger the tamper
protection indicator such that the TOE incorrectly indicates that it is operating in a tampered state.
The TOE is designed so that access to the TOE firmware, software, or its memory via its accessible
ports is prevented. No access is available to modify the TOE or its memory. To mitigate the risk that
a potential attacker will tamper with a TOE and then reprogram it with altered functionality, the
compliant TOE external and internal interfaces are locked for code read and write. The
programmable components of the TOE’s programming ports are permanently disabled for both read
and write operations. The TOE’s operational code may not be upgradeable through any of the TOE
external or internal ports.
[O.NO_TOE_ACCESS]: FPT_NTA_EXT.1
The TOE is designed to prevent any physical or logical access its internal memory. All TOE
microcontrollers run from internally protected flash memory. The TOE firmware is read/write
protected, inaccessible by JTAG interfacing, and cannot be modified or updated by any external tools.
All firmware is executed on SRAM and protected against external access/modification of code or
stacks.
The only memory access that is granted to external entities are the following:
- Connected computers may read the EDID memory
- Authorized administrators may read memory related to the TOE’s configuration data,
settings, and logging data.
[O.TAMPER_EVIDENT_LABEL]: FPT_PHP.1
Each TOE has one uniquely labeled front panel holographic tamper evident label (TEL) placed over
the boundary between the upper and lower half of the TOE enclosure. The TEL has a recorded unique
serial number that is monitored for TOE authentication purposes. Any attempt to access the internals
of the TOE will cause permanent visible damage to the TEL.
[O.ANTI_TAMPERING]: FPT_PHP.1 FPT_PHP.3
In addition to the TEL on the front panel, the TOE is physically designed to trigger the anti-tampering
system once opened. The TOE enclosure is composed of all-around reinforced stainless steel
construction, which shields it from outside intrusion through brute physical force. There is also a
3
See section 1.6.2.6.3 above for detailed information about Restore Factory Default (reset)
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mechanical switch on the inside of the TOE that triggers the anti-tampering state when the enclosure
is manually opened.
Once the anti-tampering state is triggered, the TOE is permanently disabled. There is no access
available to reset the TOE to factory defaults once the anti-tampering state is active. All channels are
electrically and logically isolated by setting all TOE multiplexers to isolation and opening all data
relays. All stored information on the TOE is also erased.
When the anti-tampering system is triggered, the TOE shuts down all ports and functionality. The
following user indications occur once the anti-tampering system is triggered:
1. All the push-button LEDs flash repeatedly
2. Alarm from internal speaker beeps repeatedly
3. Relays on the TOE pulse repeatedly
The TOE power supply controls the anti-tampering system during powered operation. When the TOE
is not supplied with external power, a backup battery located on the TOE circuit board keeps the anti-
tampering system powered. The battery is rated for an operational life of 10 years, but this is
extended when the TOE is externally powered as the battery depletion rate is reduced in this case.
The TOE has a non-volatile battery controller that is powered by both the backup battery and the
power supply of the TOE, depending on whether or not the TOE is externally powered. The data
retention voltage of this controller is between 1V and 5V. If the voltage of the backup battery depletes
below 1V, the anti-tampering function will be triggered, either immediately upon detection if the TOE
is powered on, or on the first boot after detection if the TOE is powered off when the depletion
threshold is reached. This permanently disables the TOE.
6.4 TOE Self-Testing
[O.SELF_TEST]: FPT_TST.1
All TOEs have a self-testing function that executes immediately after power is supplied including
Restore Factory Default (reset) and power reset, before normal operation access is granted to the
user. Self Test function includes the following activities:
1. Basic integrity test of the TOE hardware (no front panel push buttons are jammed).
2. Basic integrity test of the TOE firmware.
3. Integrity test of the anti-tampering system and control function.
a. Ensure the calendar date had been set.
b. Ensure the anti-tamper switches had not been opened when powered off.
c. Ensure the anti-tamper switches are currently closed.
d. Ensure the anti-tamper battery had not been tampered with when powered off.
e. Ensure the anti-tamper battery is still intact.
4. Ensure the isolation between HID traffic of each computer.
5. Ensure the isolation of HID traffic between different computers.
Users verify the integrity of the TSF and its data through these mechanisms. All features of the TOE
front panel are tested during power up self-testing. From power up until the termination of the TOE
self-test, no channel is selected. This ensures no TOE state is enabled to the user until all self tests
have been passed. If all self tests are passed, normal operation is indicated audibly through one beep
of the internal alarm followed by one pulse of an internal relay. If any self-tests fail, the TOE is
temporarily disabled to the extent that all computer and peripheral ports are deactivated, and the
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management interface cannot be accessed. The user can reboot the TOE (power off/power on) to
attempt to clear the error state.
[O.SELF_TEST_FAIL_TOE_DISABLE]: FPT_FLS_EXT.1, FPT_TST_EXT.1
If a self-testing function does not meet normal operation requirements (failure), the TOE is
temporarily disabled until the issue is resolved and the TOE is rebooted (power off/power on). If the
unit is permanently defective, then it must be replaced.
[O.SELF_TEST_FAIL_INDICATION]: FPT_TST_EXT.1
If self-testing fails, all front panel LEDs will turn on to indicate self test failure. TOE normal
operation is disabled until the issue is resolved and the system is rebooted. When the system passes
all self-testing functions, normal operation is indicated by one beep from the internal speaker and
one pulse from an internal TOE relay.
6.5 TOE Audio Subsystem Security Functions
The TOE enforces requirements for data isolation and peripheral authorization for the analog audio
output interface.
[O.COMPUTER_INTERFACE_ISOLATION,
O.COMPUTER_INTERFACE_ISOLATION_TOE_UNPOWERED, O.USER_DATA_ISOLATION,
O.PERIPHERAL_PORTS_ISOLATION, O.REJECT_UNAUTHORIZED_PERIPHERAL]:
FDP_APC_EXT.1/AO, FDP_PDC_EXT.1, FDP_PDC_EXT.2/AO, FDP_PUD_EXT.1
When the TOE is not powered, an audio isolation relay is opened to isolate the audio input ports from
all internal TOE circuitry. The TOE does not supply power to any device connected to the analog audio
output interface. Each connected computer has its own isolated stereo audio channel that flows from
the connected computer's audio input port to the analog stereo output port of the TOE. The analog
audio output interface is the only physical interface for this function; unauthorized peripherals are
either physically incompatible or logically incompatible (as is the case with audio input devices).
[O.UNIDIRECTIONAL_AUDIO_OUT]: FDP_AFL_EXT.1, FDP_APC_EXT.1/AO,
FDP_UDF_EXT.1/AO
The use of microphones as input devices is prohibited. All TOE devices support analog audio out
switching and all TOE devices will prevent microphone devices. These microphones are stopped
through the use of uni-directional audio diodes on both left and right stereo channels (forces data
flow from only the computer to the connected audio device) and the LM4880 Boomer analog output
amplifier which enforces uni-directional audio data flow. All audio signals are filtered in accordance
with the Audio Filtration Specifications table (Table 25) above.
The audio system is protected mechanically to provide physical isolation of the audio ports to all the
remaining sources; at any given moment, only one source is connected to the audio multiplexer. This
type of physical connection ensures the complete isolation between an input computer and limits
any possible leakage. The multiplexer provides protection for channel to channel crosstalk as the off
channel will not get any audio signal when the active channel is on a high frequency. The multiplexer
is also able to control the OFF-Isolation at a level of 120 dB and channel separation at 116 dB.
Furthermore, uni-directional audio diodes are placed in parallel on both right and left stereo
channels to ensure uni-directional data flow from the connected computer to the audio analog output
port on the TOE which prevents any reverse audio from leaking. Audio data from the connected
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peripheral devices to the connected computer is blocked by the audio uni-directional electronic
circuit. Only analog audio is supported, all digital audio will be blocked using a dedicated filter. The
output signal is limited to range between 45dB and 75dB.
[O.COMPUTER_TO_AUDIO_ISOLATION]: FDP_APC_EXT.1/AO, FDP_UDF_EXT.1/AO
The TOE system controls the audio switching between each connected computer channel using
isolated unidirectional audio buses. The TOE audio interface uses a solid state multiplexer and
mechanical relays to ensure audio/computer channel isolation.
[O.NO_USER_DATA_RETENTION]: FDP_RIP_EXT.1, FDP_RIP_EXT.2
The TOE audio subsystem does not delay, store, or convert audio data flows. This prevents any audio
overflow during switching between isolated audio channels. The Letter of Volatility in Appendix B
identifies all non-volatile memory components of the TOE and the data that is stored on them; these
components do not store audio data.
[O.SELF_TEST]: FPT_TST.1
[O.SELF_TEST_FAIL_TOE_DISABLE]: FPT_FLS_EXT.1, FPT_TST_EXT.1
[O.ANTI_TAMPERING_PERMANENTLY_DISABLE_TOE]: FPT_PHP.3 and FPT_FLS.1
If the TOE fails to pass the audio self test or anti-tampering is triggered, the same audio isolation relay
is opened to isolate the audio inputs, preventing data leakage.
6.6 TOE Keyboard and Mouse Functionality
The TOE enforces requirements for data isolation and peripheral authorization for the
keyboard/mouse interface.
[O.COMPUTER_INTERFACE_ISOLATION,
O.COMPUTER_INTERFACE_ISOLATION_TOE_UNPOWERED, O.USER_DATA_ISOLATION,
O.PERIPHERAL_PORTS_ISOLATION, O.REJECT_UNAUTHORIZED_ENDPOINTS,
O.REJECT_UNAUTHORIZED_PERIPHERAL]: FDP_APC_EXT.1/KM, FDP_FIL_EXT.1/KM,
FDP_PDC_EXT.1, FDP_SWI_EXT.3
In order to completely isolate the keyboard and mouse interfacing for all connected computers, host
and device emulators are used to control these peripheral interfacings. The host emulator receives
serial commands from the USB keyboard and mouse and stores them in SRAM. These commands are
sent through the current channel to its respective isolated microcontroller (the device emulator).
The TOE device emulator then interacts with its assigned isolated connected computer via USB.
Having separate isolated device emulators assures that the connected computers do not have an
electrical or logical information channel with the TOE or peripheral devices. External devices
connected to the USB KM ports of the TOE cannot be used to supply power to the TOE.
When the TOE is in a failure state (either because it has experienced self-test failure or physical
tampering), no data will be transmitted through the TOE.
Each isolated device emulator is powered by the TOE. Each isolated host emulator is powered in
conjunction by its respective connected computer and the TOE. The host emulator is being reset
whenever the computer or the TOE are powered on. Uni-directional diodes are used to isolate all
power domains from each connected computer to each device emulator.
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In addition to device emulators for interface isolation, computer/host emulators are used by the TOE
to interact with the peripheral interfacing of connected keyboard and mouse devices. The host
emulator further isolates these peripheral devices from connected computers and TOE circuitry. Any
threat that attempts to access connected computers through peripheral keyboard and mouse devices
must bypass both the host and the device emulator for each isolated channel. The data exchange
between the host and device emulators is limited to basic keyboard and mouse commands.
A secure peripheral switch (multiplexer) is used to assure the selection of just one tied keyboard
and mouse serial data stream during TOE operation. The secure multiplexer has a third position,
isolation, which is activated when the TOE has been tampered with or self-test has failed to disable
the keyboard and mouse stream.
The keyboard and mouse processor is programmed in firmware only to accept 108-key keyboard
and 3-button mouse USB devices. Unauthorized peripheral devices will be rejected by the TOE’s
keyboard and mouse ports. Wireless keyboard and mouse are special USB composite devices; when
this type of device is recognized by the TOE, all front LED’s of the TOE will blink and the user will
need to disconnect and reboot the TOE. The only USB host peripheral devices that are allowed by
the TOE are keyboard and mouse host emulators. Basic USB 1.1/2.0 HID-class devices are
authorized as valid endpoints by the TOE. Note that devices having integrated USB hub and
composite devices will only be supported if the connected device has at least one endpoint which is
a keyboard or mouse HID class. All other non-keyboard/mouse HID class endpoints will be disabled
in this scenario. Both keyboard and mouse TOE ports are interchangeable. It is assumed based on
the claimed PP that all standard peripheral devices are untrusted; therefore, the TOE protects the
system from attacks that may be executed to exploit such devices and enable unauthorized data
flows. By creating uni-directional isolated keyboard and mouse TOE channels that are tied to the two
USB 1.1/2.0 ports on the TOE, unauthorized data flows are eliminated.
Inside the TOE, the keyboard and mouse peripherals are switched together from one isolated
connected computer to the next isolated connected computer. There is no administration
configuration that allows keyboard and mouse functionality to split into separate serial data
channels. Keyboard and mouse data flow is not connected to any other TOE data flow (audio, video)
or other external interfaces.
[O.NO_USER_DATA_RETENTION]: FDP_RIP_EXT.1, FDP_RIP_EXT.2, FDP_RIP.1/KM
TOE Non-Volatile Memory is not used to store keyboard and mouse data. All keyboard and mouse
commands are stored on Static Random Access Memory (SRAM). Since SRAM is volatile memory, all
data is cleared off the stack when the TOE is powered down and during Restore Factory Default. The
buffer for keyboard and mouse data is 128 bits and is continuously read and cleared during use.
During switching between one connected computers to another, the TOE system controller
assures that the keyboard and mouse stacks are deleted through forced removal of power from the
SRAM buffer. The switching process takes between 250 and 500 milliseconds (ms). Internal
components of the TOE temporarily shut down power to the keyboard and mouse peripherals to
ensure the elimination of any built-up of cached commands from the previous channel. This
temporary power reset prevents data leakage. In addition, the TOE deletes all keyboard and mouse
stacks upon Restore Factory Default function.
More information about the keyboard/mouse buffer and its clearing, including the physical
components responsible for doing this, can be found in Appendix B below. This Appendix also lists
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the non-volatile memory components of the TOE and the data that is stored on them to show that
the TOE does not store user data in non-volatile memory.
[O.EMULATED_INPUT]: FDP_PDC_EXT.2/KM, FDP_PDC_EXT.3/KM
Isolated host/device emulators are used to interact with the serial commands sent via keyboard and
mouse over USB. The host emulator receives a serial data stream from the tied keyboard and mouse
peripherals. This data is passed through a peripheral data diode, optical isolator, and a mechanical
relay to the device emulator. This prevents any type of bi-directional communication between the
keyboard/mouse and the connected computers.
[O.UNIDIRECTIONAL_INPUT]: FDP_UDF_EXT.1/KM
To ensure uni-directional data flow, data diodes, optical isolators, and mechanical relays are placed
in series between the TOE host emulators and device emulators. Each isolated device emulator has
its own respective diode, optical isolator and relay to assure electrical/logical data isolation from
other data channels and other TOE functions. This can be seen in the TOE by observing the embedded
keyboard LEDs of CAPS, Num, and Scroll Lock. When connected to the computer through the TOE,
these indicators are not functional as this data is not able to pass between the TOE and the computer
and vie-versa. Thus, the use of these embedded keyboard LEDs is not supported by the TOE.
[O.SELF_TEST]: FPT_TST.1
[O.SELF_TEST_FAIL_TOE_DISABLE]: FPT_FLS_EXT.1, FPT_TST_EXT.1
[O.ANTI_TAMPERING_PERMANENTLY_DISABLE_TOE]: FPT_PHP.3 and FPT_FLS.1
When the TOE is not powered, an isolation relay is opened to isolate the KM input ports from all
internal TOE circuitry. If the TOE fails to pass the KM self test or anti-tampering is triggered, the same
isolation relay is opened to isolate the KM inputs, preventing data leakage. All stored keyboard and
mouse information is erased from the TOE.
6.7 TOE Video Subsystem Security Functions
The TOE enforces requirements for data isolation and peripheral authorization for the video
interface.
The TOE video data flow path is composed of three uni-directional paths:
• Read EDID path
• Write EDID path
• Uni-directional video path
The TOE is designed to read the connected monitor’s EDID upon power up for a short period of time.
The monitor must be connected to the video output connector located in the console space at the
back of the TOE.
If the read EDID from the connected monitor is identical to the current stored EDID in the TOE then
EDID write function will be skipped.
The TOE indicates current EDID read/write processes to the user by flashing the front panel’s LEDs.
Port one green and push button blue LEDs will both begin to flash for about 10 seconds. When the
LEDs stop flashing, the EDID data has been read by the processor and has been written to all EDID
emulators for each connected computer video channel. If the TOE has more than one video board (in
the case of dual-head models), then the TOE will continue to read/write the EDIDs of the connected
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monitors and indicate the progress of the process by flashing the next port selections green and push
button blue LEDs respectively. Table 27 below shows a time estimate for EDID read/write for all TOE
models.
Single Head Dual Head
2-Port 10 20
4-Port 10 20
8-Port 10 20
Table 27 – EDID Read/Write Time Chart
EDID READ
During EDID read, the EDID I2C isolation switch closes and EDID data is read from the EDID EEPROM
of the monitor by the TOE processor. The EDID multiplexer is set its isolated option to establish
electrical and physical isolation between the processor and the rest of the TOE EDID emulators,
preventing possible bi-directional communication between the monitor and TOE. Note: all
computers must be disconnected from the TOE before attempting to read/write EDID information.
EDID Write
The I2C isolation switch between the EDID EEPROM on the monitor and the TOE processor is opened
to prevent any bi-directional communication between the connected computers and the TOE. The
EDID multiplexer is then set to the first EDID emulator of the TOE. The processor then transmits the
EDID data to the EDID emulator. Once the EDID data has been transmitted, the EDID multiplexer
switches to the next EDID emulator. The process repeats itself until the processor has written to all
EDID emulators in the TOE.
Normal Operation
All attempted threats made from a connected computer to the TOE will be stopped by the TOE
architecture. Each connected computer video channel has its own emulated EDID EEPROM chip. Each
independent EDID EEPROM chip isolates all video data provided by the connected computers.
The following features implemented in the TOE video subsystem (depending on the video protocols
supported):
[O.COMPUTER_INTERFACE_ISOLATION,
O.COMPUTER_INTERFACE_ISOLATION_TOE_UNPOWERED, O.USER_DATA_ISOLATION,
O.PERIPHERAL_PORTS_ISOLATION]: FDP_APC_EXT.1/VI
Each connected computer has its own TOE isolated channel with its own EDID emulator and video
input port. Data flows from the input video source through its respective EDID emulator and out of
the monitor display port. Each video input interface is isolated from one another using different EDID
ICs, power planes, ground planes, and electronic components in each independent channel.
When the TOE is in a failure state (either because it has experienced self-test failure or physical
tampering), no data will be transmitted through the TOE.
[O.REJECT_UNAUTHORIZED_PERIPHERAL]: FDP_PDC_EXT.1, FDP_PDC_EXT.2/VI
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To ensure the EDID signal cannot be used to transfer unauthorized data, the TOE has the following
limitations on EDID:
• The EDID is only learned on power up of the TOE and only from the display.
• During the learning process, all EDID signals are disconnected from the computers and the
computers all have hot plug disabled.
• Each computer has a dedicated EEPROM for storing the EDID data. This EEPROM is limited
to be Read-Only by the computer and has only 256 bytes of storage, the computer cannot edit
it and it can be read only using the protocol of the EDID with its limitations.
• When the learning process is complete, each computer is connected to the Read-Only EDID
flash memory. The reading is initiated by the computer after the TOE has completed the
learning and programming of the flashes to all the computer ports.
• The transition of the Hotplug signal from “disabled” during learning process triggers the
computer to read from the dedicated flash memory of the TOE through the DDC.
• For each supported display protocol, the TOE permits communication of EDID and HPD
information from display to computer.
All TOE models support DP 1.2 video input and output. The TOE will convert the DP signal to HDMI
inside the TOE. This signal is then converted back to DisplayPort for output to console display. The
TOE rejects communication of EDID information from computer to display, as well as CEC, HDCP, and
MCCS communications. Link Training is allowed for the DisplayPort interface.
[O.AUTHORIZED_USAGE]: FDP_CDS_EXT.1
The TOE supports connected displays from a single source video feed (either single-head or dual-
head). Because of this, the single selected source video feed is always the same channel as all other
peripherals, and indication of the selected channel is indicated through the channel selection LEDs
on the TOE chassis. This functionality relates to unauthenticated users operating the TOE so it does
not relate to the portion of the O.AUTHORIZED_USAGE objective that is satisfied by the
administration capability described in section 6.2 above.
[O.UNIDIRECTIONAL_VIDEO]: FDP_UDF_EXT.1/VI
For each supported video protocol, the TOE forces native Analog video data (red, green, and blue
channels) and TMDS digital video data (1 Clock signal, red, green, blue channels) to unidirectional
flow from the switched computer to the connected display device (or devices, if the TOE supports
dual-head and multiple displays are connected to the TOE’s console ports).
[O.SELF_TEST]: FPT_TST.1
[O.SELF_TEST_FAIL_TOE_DISABLE]: FPT_FLS_EXT.1, FPT_TST_EXT.1
[O.ANTI_TAMPERING_PERMANENTLY_DISABLE_TOE]: FPT_PHP.3 and FPT_FLS.1
When TOE is unpowered, all video signals are isolated electrically and logically from the TOE. If the
TOE anti-tampering is triggered or TOE self-testing has failed, the same video signal isolation occurs
inside the TOE. The emulated EDID EEPROMs are still powered by their respective computers, but
cannot communicate with the TOE due to hardware component isolation.
[O.ANTI_TAMPERING]: FPT_PHP.3 and FPT_FLS.1
If anti-tampering is triggered on the TOE, all video channels are permanently isolated and all EDID
information is erased from the TOE.
[O.NO_USER_DATA_RETENTION]: FDP_RIP_EXT.1
No data is stored by the TOE in regards to user video data (as opposed to EDID data that is used to
interface with a connected video peripheral). The Letter of Volatility in Appendix B identifies all
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non-volatile memory components of the TOE and the data that is stored on them; these components
do not store buffered video data.
[O.REJECT_UNAUTHORIZED_PERIPHERAL]: FDP_PDC_EXT.1, FDP_PDC_EXT.2/VI,
FDP_PDC_EXT.3/VI, FDP_IPC_EXT.1, FDP_SPR_EXT.1/DP
The TOE rejects unauthorized video peripherals through the physical port and filtering of video
signals received. Physically, the TOE will only accept a video connector which fits specifications of
the unit, which is DisplayPort for P models. The connectors that are not for the specified unit will not
be able to connect and send signals to the TOE. The Pin out for each video interface is different which
ensures that no other physical connector can be used. The video signals themselves are also ensured
to adhere to the specifications. A VGA signal, for example, is analog and cannot be read by the digital
standard of DisplayPort. The TMDS signal of HDMI and DVI cannot be read by the DisplayPort
interface. The power level and the HPD signal for the various connections are also different across
the board which will reduce any risk. Another thing to note the PC in the system is specifically an
input device and can only receive certain signals from the monitor. On top of these obstructions, the
TSF ensures that any signal which does not match the protocol of the intended video signal depending
on the device, will be completely ignored by the TOE.
The DisplayPort AUX channel between the PC and the monitor is completely disconnected. The AUX
channel from the computer is connected to an internal FPGA that simulates a monitor. The simulated
AUX is preloaded in the FPGA during manufacturing and can never be changed.
[O.PROTECTED_EDID]: FDP_PDC_EXT.2/VI, FDP_SPR_EXT.1/DP
The TOE video subsystem prevents MCCS write commands through independent, read only emulated
EDID EEPROMs. The TOE processor reads the EDID data from the monitor and then individually
writes this EDID data to the emulator during power up. All changes in display after the EDID
read/write process are ignored. There are switches in the internal circuitry to prevent the connected
computer from writing to its EDID emulator. The TOE will reject invalid EDID display devices,
regardless of which physical device types are supported by the particular TOE model.
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Appendix A – Product’s Model Name Structure
KVM
XXX- XXX X XX
CK4 = CyberKVM NIAP 4.0 P=DP 1=Single Head 02=2 Port
2=Dual Head 04=4 Port
08=8 Port
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Appendix B – Letter of Volatility
Main PCBA: USB
Device: Controller Board Main MCU - ATxmega256A3U-AU
Manufacturer: Atmel
Type: Microcontroller
Functions:
The Controller Board Main MCU is responsible for controlling the operations of the USB, Keyboard
and Mouse, and front panel board. It also is responsible for communications with the Video board.
No other source can independently power the Controller Board Main MCU other than the TOE.
Memory type:
1. Flash Firmware 4KB EEPROM, 256KB Programmable Flash (non-volatile):
• All Main MCU firmware that controls its operation is saved in its own dedicated
flash memory. This firmware cannot be changed by any user or programmer. All
Main MCU firmware is erased if anti-tampering is triggered.
2. User 2KB EEPROM Flash (non-volatile):
• The Main MCU has dedicated flash EEPROM to save all registration of USB devices,
and a log of operations.
3. SRAM (volatile):
• The Main MCU uses SRAM memory to run the entire TOE system. The SRAM is
erased as soon as the external power supply is disconnected. All SRAM is erased if
anti-tampering is triggered. No user data is stored inside the SRAM when the power
is disconnected from the TOE, or if anti-tampering has been triggered.
The Controller Board Main MCU contains a 128-bit data buffer for keyboard and mouse input. The
contents of this buffer are continuously read and cleared. When a switching operation is initiated,
the buffer is immediately erased prior to the switch being performed. The erasure is performed by
the triggering of an AP2146 power switch that supplies power to the buffer. When the switch
operation is initiated the power is removed for 1ms, causing the data to be wiped.
When the Restore Factory Default operation is performed, all the user memory will be erased and
brought back to its initial state.
Device: Emulation MCU - PIC18F25J50-I/SS
Manufacturer: Microchip
Type: Microcontroller
Functions:
The Emulation MCU controls all USB device emulation and communication between the Controller
Board Main MCU and the USB connections of the TOE connected computers. No other source can
independently power the Emulation MCU other than the TOE.
Memory type:
1. Flash Firmware 32KB Programmable Flash (non-volatile):
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• All Emulation MCU firmware that controls its operation is saved in its own
dedicated flash memory.
2. SRAM (volatile):
• The Emulation MCU uses SRAM memory to run USB device emulation. The SRAM is
erased as soon as the external power supply is disconnected. All SRAM is erased if
anti-tampering is triggered. No user data is stored inside the SRAM when the power
is disconnected from the TOE, or if anti-tampering has been triggered.
Note: No flash ROM is dedicated to the Emulation MCU to save any data or log.
When the Restore Factory Default operation is performed, or power reset is initiated, or USB cable
is disconnected from the computer, all the working memory of Emulation MCU is reset to default.
The main function of this device is the emulate keyboard and mouse only. All the memory/RAM
needed is for internal operation and not related to any user data.
Device: Keyboard and Mouse USB Host Controller - SL811HS and ARM Cortex
Manufacturer: Cypress, ST
Type: USB Host processor
Functions:
The Keyboard and Mouse USB Host Controller is responsible for controlling the USB protocol,
storing the device information of the connected keyboard and mouse, and communicating with the
Controller Board Main MCU. The Keyboard and Mouse USB Host Controller ties both keyboard and
mouse serial transmissions into one line and transfers them to the Main MCU before emulation. No
other source can independently power the Keyboard and Mouse USB Host Controller other than the
TOE.
Memory Type:
1. SRAM (volatile):
• The Keyboard and Mouse USB Host Controller uses SRAM memory to store USB
Keyboard and Mouse peripheral commands and USB keyboard and mouse device
information. The SRAM is erased after each designated TOE channel switch to purge
any stored keyboard and mouse commands. The SRAM is erased as soon as the
external power supply is disconnected. All SRAM is erased if anti-tampering is
triggered. No user data is stored inside the SRAM when the power is disconnected
from the TOE, or if anti-tampering has been triggered.
Note: No flash ROM is dedicated to the KM USB Host Controller to save any data or log.
When the Restore Factory Default operation is performed, or power reset is initiated, or USB
keyboard or mouse is disconnected from the TOE, all the working memory of KM USB Host
Controller is reset to default. The main function of this device is to read the keyboard and mouse
and convert to secure internal communication. All the memory/RAM needed is for internal
operation and not related to any user data.
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Video PCBA: DP
Device: Video Board Main MCU - ATxmega256A3U-AU and STM32 ARM
Manufacturer: Atmel, ST
Type: Microcontroller
Functions:
The Video Board Main MCU is responsible for all the operations of the video board, and
communications with the Controller Board Main MCU. All devices on the video board are controlled
by the Video Board Main MCU. No other source can independently power the Video Board Main
MCU other than the TOE.
Memory type:
1. Flash Firmware 2KB EEPROM, 64KB Programmable Flash (non-volatile):
• All Video Board Main MCU firmware that controls its operation is saved in its own
dedicated firmware flash block. This firmware cannot be changed by any user or
programmer. Video Board Main MCU firmware is erased if anti-tampering is
triggered.
2. SRAM (volatile):
• The Video Board Main MCU uses SRAM memory to run the entire video board
during TOE operation. The SRAM is erased as soon as the external power supply is
disconnected. All SRAM is erased if anti-tampering is triggered. No user data is
stored inside the SRAM when the power is disconnected from the TOE, or if anti-
tampering has been triggered.
When the Restore Factory Default operation is performed, all the user memory will be erased and
brought back to its initial state.
Device: EDID Emulator
Manufacturer: Atmel - AT24C04C-SSHM-T, Atmel - AT24C08C-SSHM-T, Microchip - 24LC04B-
I/SN, Microchip - 24LC08B-I/SN
Type: EEPROM
Functions:
The EDID Emulator is responsible for all EDID storage, used for emulation on the video board. All
the EDID emulators are powered by their respective computers or the TOE, however all
communications channels are disabled if TOE is not powered.
Memory - Atmel - AT24C04C-SSHM-T or Microchip - 24LC04B-I/SN (non-volatile):
• SERIAL 4KBIT 400KHZ EEPROM
• The EDID EEPROM is 4K bit electrically erasable
• Programmable memory (EEPROM), organized as 512 x 8 bits.
Memory - Atmel - AT24C08C-SSHM-T or Microchip - 24LC08B-I/SN (non-volatile):
• SERIAL 8KBIT 400KHZ EEPROM
• The EDID EEPROM is 8K bit electrically erasable
• Programmable memory (EEPROM), organized as 1024 x 8 bits.
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When the Restore Factory Default operation is performed, all the EDID information stored in the
local memory is erased and brought to its initial state. After first operation, the TOE will detect a
new display, all computers will be disconnected, and the TOE will learn the new display, store in its
EDID memory for each computer.
Front Panel PCBA
The front panel board has no ROM or RAM functionality.