Secure Kernel Code Integrity Security Policy Document
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Microsoft Windows
FIPS 140 Validation
Microsoft Windows 10 (Creators Update, Fall Creators Update,
April 2018 Update)
Microsoft Windows Server (versions 1703, 1709, and 1803)
Non-Proprietary
Security Policy Document
Version Number 1.4
Updated On April 4, 2019
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This Security Policy is non-proprietary and may be reproduced only in its original entirety (without revision).
The information contained in this document
represents the current view of Microsoft Corporation
on the issues discussed as of the date of publication.
Because Microsoft must respond to changing market
conditions, it should not be interpreted to be a
commitment on the part of Microsoft, and Microsoft
cannot guarantee the accuracy of any information
presented after the date of publication.
This document is for informational purposes only.
MICROSOFT MAKES NO WARRANTIES, EXPRESS
OR IMPLIED, AS TO THE INFORMATION IN THIS
DOCUMENT.
Complying with all applicable copyright laws is the
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© 2018 Microsoft Corporation. All rights reserved.
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The names of actual companies and products
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Version History
Version Date Summary of changes
1.0 October 3, 2017 Draft sent to NIST CMVP
1.1 November 18, 2017 Updates for Windows 10 version 1709
1.2 May 1, 2018 Editing updates
1.3 October 22, 2018 Updates for Windows 10 version 1803
1.4 April 4, 2019 Updates for additional validated platforms
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TABLE OF CONTENTS
SECURITY POLICY DOCUMENT.....................................................................................................1
VERSION HISTORY..............................................................................................................................3
1 INTRODUCTION...................................................................................................................6
1.1 LIST OF CRYPTOGRAPHIC MODULE BINARY EXECUTABLES..................................................................6
1.2 VALIDATED PLATFORMS............................................................................................................6
2 CRYPTOGRAPHIC MODULE SPECIFICATION...........................................................................9
2.1 CRYPTOGRAPHIC BOUNDARY......................................................................................................9
2.2 FIPS 140-2 APPROVED ALGORITHMS ..........................................................................................9
2.3 NON-APPROVED ALGORITHMS .................................................................................................10
2.4 FIPS 140-2 APPROVED ALGORITHMS FROM BOUNDED MODULES ....................................................10
2.5 CRYPTOGRAPHIC BYPASS.........................................................................................................11
2.6 HARDWARE COMPONENTS OF THE CRYPTOGRAPHIC MODULE..........................................................11
3 CRYPTOGRAPHIC MODULE PORTS AND INTERFACES ..........................................................11
3.1 SKCI EXPORT FUNCTIONS........................................................................................................11
3.1.1 SKCIINITIALIZE.................................................................................................................................12
3.1.2 SKCICREATECODECATALOG...............................................................................................................12
3.1.3 SKCICREATESECUREIMAGE................................................................................................................12
3.1.4 SKCIVALIDATEIMAGEDATA................................................................................................................12
3.1.5 SKCIVALIDATEDYNAMICCODEPAGES...................................................................................................12
3.1.6 SKCIFINALIZESECUREIMAGEHASH.......................................................................................................13
3.1.7 SKCIFINISHIMAGEVALIDATION ...........................................................................................................13
3.1.8 SKCIFREEIMAGECONTEXT .................................................................................................................13
3.1.9 SKCITRANSFERVERSIONRESOURCE .....................................................................................................13
3.1.10 SKCIMATCHHOTPATCH ....................................................................................................................13
3.2 CONTROL INPUT INTERFACE .....................................................................................................13
3.3 STATUS OUTPUT INTERFACE.....................................................................................................13
3.4 DATA INPUT INTERFACE ..........................................................................................................13
3.5 DATA OUTPUT INTERFACE .......................................................................................................13
4 ROLES, SERVICES AND AUTHENTICATION...........................................................................14
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4.1 ROLES.................................................................................................................................14
4.2 SERVICES.............................................................................................................................14
4.3 AUTHENTICATION..................................................................................................................16
5 FINITE STATE MODEL.........................................................................................................16
5.1 SPECIFICATION......................................................................................................................16
6 OPERATIONAL ENVIRONMENT...........................................................................................17
6.1 SINGLE OPERATOR.................................................................................................................17
6.2 CRYPTOGRAPHIC ISOLATION.....................................................................................................17
6.3 INTEGRITY CHAIN OF TRUST .....................................................................................................18
7 CRYPTOGRAPHIC KEY MANAGEMENT................................................................................21
8 SELF-TESTS........................................................................................................................21
9 DESIGN ASSURANCE..........................................................................................................21
10 MITIGATION OF OTHER ATTACKS.......................................................................................22
11 SECURITY LEVELS...............................................................................................................23
12 ADDITIONAL DETAILS ........................................................................................................23
13 APPENDIX A – HOW TO VERIFY WINDOWS VERSIONS AND DIGITAL SIGNATURES ...............24
13.1 HOW TO VERIFY WINDOWS VERSIONS .......................................................................................24
13.2 HOW TO VERIFY WINDOWS DIGITAL SIGNATURES .........................................................................24
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1 Introduction
Secure Kernel Code Integrity (SKCI) is a code integrity mechanism that runs in the Virtual Secure Mode
(VSM) of the Windows Hyper-V hypervisor. SKCI is implemented in a Dynamic Link Library (DLL) file,
SKCI.DLL.
Code Integrity and Secure Kernel Code Integrity are closely related modules that are used, depending on
configuration of Windows, to validate system and application binaries.
Two Windows configuration options dictate whether Code Integrity or Secure Kernel Code Integrity are
used to verify a binary image:
 Virtual Secure Mode (VSM), also known as Core Isolation: Windows can use the Hypervisor to
start an execution environment, called the Secure Kernel, that can enforce additional security
rules. When VSM is configured, Secure Kernel Code Integrity verifies the integrity of critical user-
mode modules such as BCRYPTPRIMITIVES.DLL instead of the Code Integrity module.
 Hypervisor Code Integrity (HVCI) , also known as Memory Integrity: This feature depends on
VSM. When enabled, all drivers loaded into the Windows kernel are integrity verified by Secure
Kernel Code Integrity.
This Security Policy Document assumes that the following hardware prerequisites are available:
 UEFI Secure Boot is available and enabled
 Trusted Platform Module (TPM)
 Hardware virtualization support (VT-x or AMD-V)
Additionally, VSM must be configured for SKCI.DLL to be loaded and used.
1.1 List of Cryptographic Module Binary Executables
Secure Kernel Code Integrity cryptographic module contains the following binary:
 skci.dll
The Windows builds covered by this validation are:
 Windows 10 version 1703, build 10.0.15063
 Windows 10 version 1709 and Windows Server version 1709 build 10.0.16299
 Windows 10 version 1803 and Windows Server version 1803 build 10.0.17134
1.2 Validated Platforms
The Windows editions covered by this validation are:
 Microsoft Windows 10 Pro Edition (64-bit version)
 Microsoft Windows 10 Enterprise Edition (64-bit version)
 Microsoft Windows 10 Education Edition (64-bit version)
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 Microsoft Windows 10 S Edition (64-bit version)
 Windows Server Standard Core
 Windows Server Datacenter Core
SKCI was validated using the combination of computers and Windows operating system editions
specified in the table below.
All the computers for Windows 10 and Windows Server listed in the table below are all 64-bit Intel
architecture and implement the AES-NI instruction set but not the SHA Extensions. The exceptions are:
 Dell Inspiron 660s - Intel Core i3 without AES-NI and SHA Extensions
 HP Slimline Desktop - Intel Pentium with AES-NI and SHA Extensions
Table 1 Validated Platforms for Windows 10 Creators Update, Fall Creators Update and Windows Server
Computer
Windows
10
Home
Windows
10
Pro
Windows
10
Enterprise
Windows
10
Education
Surface
Hub
Windows
10
S
Windows
10
Mobile
Windows
Server
Standard
Windows
Server
Datacenter
Microsoft Surface Book 2 √1
Microsoft Surface Laptop √2
√2
√2
Microsoft Surface Pro √2
√2
√2
Microsoft Surface Book √2
Microsoft Surface Pro 4 √2
Microsoft Surface Pro 3 √2
Microsoft Surface 3 with
LTE
Microsoft Surface Studio √2
Windows Server 2016
Standard Edition Hyper-V3
√2
Microsoft Lumia 950
Microsoft Lumia 950 XL
Microsoft Lumia 650
Dell Latitude 5285 √2
Dell Latitude 5290 √2
Dell Inspiron 660s
Dell Precision Tower
5810MT
√2
√1
√1
1
Tested on Windows 10 version 1709
2
Tested on Windows 10 versions 1703 and 1709
3
Tested on Surface Pro 4 hardware platform
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Dell PowerEdge R630 √2
√1
√1
Dell PowerEdge R740 √1
√1
HP Elite X3
HP Compaq Pro 6305 √2
HP Pro x2 612 G2
Detachable PC with LTE
√2
HP Slimline Desktop4
√2
Panasonic Toughbook √2
Microsoft Surface 3
Windows Server Standard
Core Hyper-V5
√1
√1
Microsoft Surface Hub
Table 2 Validated Platforms for Windows 10 and Windows Server version 1803
Computer Windows
10 Home
Windows
10 Pro
Windows
10
Enterprise
Windows
10
Education
Windows
Server
Standard
Windows
Server
Datacenter
Microsoft
Surface Go √
Microsoft
Surface Book 2
√ √
Microsoft
Surface Pro LTE
√ √
Microsoft
Surface Laptop
√ √ √
Microsoft
Surface Studio
√
Windows
Server Standard
Core Hyper-V6
√ √
Windows
Server 2016
Hyper-V7
√
Dell Latitude
5290
√
Dell Latitude 12
Rugged Tablet
√
4
This platform includes an Intel Pentium processor that implements the Intel SHA Extensions.
5
Tested on Dell 5810MT hardware platform
6
Hardware platform: Dell Precision Tower 5810MT
7
Hardware platform: Dell PowerEdge R740
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Computer Windows
10 Home
Windows
10 Pro
Windows
10
Enterprise
Windows
10
Education
Windows
Server
Standard
Windows
Server
Datacenter
Dell Inspiron
660s
Dell PowerEdge
R740
√ √
HP Pro x2 612
G2 Detachable
PC with LTE
√
HP Slimline
Desktop
√
Microsoft
Surface Pro 6
√
Microsoft
Surface Laptop
2
√
Microsoft
Surface Studio 2
√
2 Cryptographic Module Specification
Secure Kernel Code Integrity is a multi-chip standalone module that operates in FIPS-approved mode
during normal operation of the computer and Windows operating system.
The following configurations and modes of operation will cause Secure Kernel Code Integrity to operate
in a non-approved mode of operation:
 Boot Windows in Debug mode
 Boot Windows with Driver Signing disabled
 Windows enters the ACPI S4 power state (for Windows 10 version 1803 only)
2.1 Cryptographic Boundary
The software binary that comprises the cryptographic boundary for Secure Kernel Code Integrity is
SKCI.DLL.
2.2 FIPS 140-2 Approved Algorithms
SKCI implements the following FIPS 140-2 Approved algorithms:8
Algorithm Windows 10
version 1703
Windows 10 and
Windows Server
version 1709
Windows 10 and
Windows Server
version 1803
8
This module may not use some of the capabilities described in each CAVP certificate.
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FIPS 186-4 RSA PKCS#1 (v1.5)
digital signature verification
with 1024, 2048, and 3072
moduli; supporting SHA-1,
SHA-256, SHA-384, and SHA-
512
#2522 #2668 #3080
FIPS 180-4 SHS SHA-1, SHA-256,
SHA-384, and SHA-512 #3790 #4009 #4633
2.3 Non-Approved Algorithms
Secure Kernel Code Integrity only implements approved algorithms.
2.4 FIPS 140-2 Approved Algorithms from Bounded Modules
A bounded module is a FIPS 140 module which provides cryptographic functionality that is relied on by a
downstream module. As described in the Integrity Chain of Trust section, Secure Kernel Code Integrity
depends on the following modules and algorithms:
The Windows OS Loader version 1703 (module certificate #3090) provides:
 CAVP certificate #2523 for FIPS 186-4 RSA PKCS#1 (v1.5) digital signature verification with 2048
moduli; using FIPS 180-4 SHA-256
 CAVP certificate #3790 using FIPS 180-4 SHA-256
The Windows OS Loader version 1709 (module certificate # 3194) provides:
 CAVP certificate # 2674 (Windows 10 and Windows Server) for FIPS 186-4 RSA PKCS#1 (v1.5)
digital signature verification with 2048 moduli; supporting SHA-256
 CAVP certificate # 4009 (Windows 10 and Windows Server) for FIPS 180-4 SHS SHA-256
The Windows OS Loader version 1803 (module certificate #3480) provides:
 CAVP certificate # 3081 (Windows 10 and Windows Server) for FIPS 186-4 RSA PKCS#1 (v1.5)
digital signature verification with 2048 moduli; supporting SHA-256
 CAVP certificate # 4633 (Windows 10 and Windows Server) for FIPS 180-4 SHS SHA-256
The Windows Resume version 1703 (module certificate #3091) decrypts and restores the encrypted
memory state during a boot from hibernation, which acts to preserve the module’s integrity (established
by the Windows OS Loader) across hibernations:
 CAVP certificate #4624 for FIPS 197 AES CBC 128, 192 and 256, SP 800-38E AES XTS 128 and 256
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The Windows Resume version 1709 (module certificate #3091) decrypts and restores the encrypted
memory state during a boot from hibernation, which acts to preserve the module’s integrity (established
by the Windows OS Loader) across hibernations:
 CAVP certificate #4897 for FIPS 197 AES CBC 128, 192 and 256, SP 800-38E AES XTS 128 and 256
Note that the validated platforms listed in section 1.2 include processors that support AES-NI. This
module does not implement AES, but the bounded modules may implement AES and, therefore, use
AES-NI.
2.5 Cryptographic Bypass
Cryptographic bypass is not supported by SKCI.
2.6 Hardware Components of the Cryptographic Module
The physical boundary of the module is the physical boundary of the computer that contains the
module. The following diagram illustrates the hardware components used by the Secure Kernel Code
Integrity module:
3 Cryptographic Module Ports and Interfaces
3.1 SKCI Export Functions
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The following list contains all the functions exported by SKCI that are imported by the Secure Kernel.
Note that SKCI is not callable outside the Secure Kernel. These functions are also explained in the
subsequent subsections.
 SkciInitialize
 SkciCreateCodeCatalog
 SkciCreateSecureImage
 SkciValidateImageData
 SkciValidateDynamicCodePages
 SkciFinalizeSecureImageHash
 SkciFinishImageValidation
 SkciFreeImageContext
 SkciTransferVersionResource
 SkciMatchHotPatch
3.1.1 SkciInitialize
SkciInitialize is the function exported by SKCI for initializing the Secure Kernel version of Code Integrity.
During this call, SKCI will get its configuration data from the Secure Kernel loader.
See Self-Tests for information regarding cryptographic self-tests.
If a self-test fails, SkciInitialize returns STATUS_INVALID_IMAGE_HASH.
3.1.2 SkciCreateCodeCatalog
This function is called to create a code catalog object. The specified address range corresponds to a
secure allocation object. It returns a catalog object. The secure allocation must be freed by SKCI when
the catalog object is deleted.
3.1.3 SkciCreateSecureImage
This function is called when a new secure image section is created. It creates a context for validating an
image. The caller specifies the type of hash algorithm that should be used to validate the image. It
returns a pointer to the validation context, which is a state block.
3.1.4 SkciValidateImageData
This function is called to validate image data. When called for a file-hashed file that is still in the loading
state, it is expected to generate the contents of page hashes. When in this mode, it will return
STATUS_SUCCESS upon success. When page hashes are no-longer being generated and instead, page
hashes have been used to verify the supplied pages, STATUS_VALID_IMAGE_HASH will be returned upon
success.
3.1.5 SkciValidateDynamicCodePages
This function is called to validate dynamic code pages that were not part of a signed image.
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3.1.6 SkciFinalizeSecureImageHash
This function is called to finalize (complete) the hash of a secure image. It returns the file or page hash of
the image.
3.1.7 SkciFinishImageValidation
This function is called when initial validation of the image is complete. It completes the image validation
process. The function is responsible to verify that the contents of the image header and/or file hash are
correct, and, if successful, should update the image state to enable subsequent validation using page
hashes. It is responsible for verifying that the data is verified by the page hashes for the resource section
only. It returns information about the signing level; how the image is signed; the catalog ID used to
validate the image; the algorithm with which a hash must be recalculated, if necessary; and the type of
image the pages may be mapped into.
3.1.8 SkciFreeImageContext
This function is called when a secure image is unloaded and the context is to be freed.
3.1.9 SkciTransferVersionResource
This function is called to process the supplied version resource for an image, so that version data can be
used during SkciFinishImageValidation.
3.1.10 SkciMatchHotPatch
This routine compares an image hash with the CI data embedded in a hot patch to determine whether
the image matches the expected hash.
3.2 Control Input Interface
The Control Input Interface for SKCI consists of the export functions. Options for control operations are
passed as input parameters to the CI export functions.
3.3 Status Output Interface
The Status Output Interface for SKCI consists of the exported functions listed in SKCI Export Functions.
The status information is returned to the caller as the return value of each function (e.g.
STATUS_SUCCESS, STATUS_UNSUCCESSFUL, STATUS_INVALID_IMAGE_HASH).
3.4 Data Input Interface
The Data Input Interface for SKCI consists of the exported functions listed in SKCI Export Functions. Data
and options are passed to the interface as input parameters to the export functions. Data Input is kept
separate from Control Input by passing Data Input in separate parameters from Control Input.
3.5 Data Output Interface
The Data Output Interface for SKCI also consists of the export functions listed in SKCI Export Functions
with the exception of the initialization and status functions. Data is returned to the function’s caller via
output parameters.
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4 Roles, Services and Authentication
4.1 Roles
Secure Kernel Code Integrity is a library used solely by the Windows Secure Kernel and does not interact
with the user through any service. The module’s functions are fully automatic and not configurable. FIPS
140 validations define formal “User” and “Cryptographic Officer” roles. Both roles can use any Secure
Kernel Code Integrity service.
4.2 Services
Secure Kernel Code Integrity’s services are:
1. Verify the integrity of binary executable code – This service is called by Secure Windows
Kernel to verify the integrity of digitally signed drivers and other critical binary components
of the operating system.
2. Show Status – The module does not provide an explicit status interface. Operational status
is indicated by successfully initializing the module using SkciInitialize and success status
messages using the binary integrity verification functions.
3. Self-Tests - The module provides a power-up self-tests service that is automatically
executed when the module is loaded into memory.
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The following table maps the services to their corresponding algorithms, critical security parameters
(CSPs), and how they are invoked.
Service / Function Algorithms CSPs Invocation
Verify the integrity
of binary executable
code
FIPS 186-4 RSA PKCS#1
(v1.5) verify with public key
FIPS 180-4 SHS:
SHA-1 hash
SHA-256 hash
SHA-384 hash
SHA-512 hash
RSA public
key
This service is fully automatic.
This service is executed
whenever a binary executable is
loaded.
Show Status None None This service is fully automatic.
This service is executed upon
completion of an integrity check
function.
Self-Tests FIPS 186-4 RSA PKCS#1
(v1.5) verify with public key
and known signature
FIPS 180-4 SHS:
SHA-1 KAT
SHA-256 KAT
SHA-512 KAT
None This service is fully automatic.
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The following table maps SKCI services and export functions.
Service Export Functions
Verify the integrity of binary executable
code
SkciCreateCodeCatalog
SkciCreateSecureImage
SkciValidateImageDataSkciValidateDynamicCodePages
SkciFinalizeSecureImageHash
SkciFinishImageValidation
SkciFreeImageContext
SkciTransferVersionResource
SkciMatchHotPatch
Show Status SkciInitialize
All exported functions
Self-Tests SkciInitialize
4.3 Authentication
The module does not provide authentication. Roles are implicitly assumed based on the services that are
executed.
5 Finite State Model
5.1 Specification
The following diagram shows the finite state model for Secure Kernel Code Integrity:
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6 Operational Environment
The operational environment for SKCI is the Windows 10 operating system running on a supported
hardware platform.
6.1 Single Operator
Secure Kernel Code Integrity is invoked by the Windows Secure Kernel as a fully automatic service with
no user interaction.
6.2 Cryptographic Isolation
In the Windows operating system, all secure kernel-mode modules, including SKCI.DLL, are loaded into
the Windows Secure Kernel which executes as a single process. The Windows operating system
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environment enforces process isolation from user-mode processes including memory and processor
scheduling between the kernel and user-mode processes.
6.3 Integrity Chain of Trust
Windows uses several mechanisms to provide integrity verification depending on the stage in the OS
boot sequence and also on the hardware and OS configuration. The following diagram describes the
Integrity Chain of trust for each supported configuration for the following versions:
 Windows 10 version 1703, build 10.0.15063
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The following diagram describes the Integrity Chain of trust for each supported configuration for the
following versions:
 Windows 10 and Windows Server version 1709 and 1803:
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BCryptPrimitives.dll
BitLocker Dump
Filter
(DumpFVE.sys)
Virtual TPM
(TPMEng.dll)
Code Integrity
(CI.dll)
Secure Kernel Code
Integrity (SKCI.dll)
CNG.sys
Windows Resume (WinResume.efi)
Windows OS Loader (WinLoad.efi)
Boot Manager (BootMgr.efi)
UEFI
When Secure Boot is enabled, UEFI validates
Not enabled
Enabled
Memory Integrity
Core Isolation not enabled
Core Isolation enabled
Refer to the Introduction for information on the relationship between Code Integrity and Secure Kernel
Code Integrity.
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7 Cryptographic Key Management
Secure Kernel Code Integrity does not generate or store any persistent cryptographic keys; and uses RSA
public keys for validating file integrity.
8 Self-Tests
The Secure Kernel Code Integrity module implements Known Answer Test (KAT) functions each time the
module is loaded by the Windows kernel.
Secure Kernel Code Integrity performs the following power-on (startup) self-tests:
 SHS (SHA-1) Known Answer Test
 SHS (SHA-256) Known Answer Test
 SHS (SHA-512) Known Answer Test
 RSA verify using a verify test with a Known Signature of the PKCS#1 v1.5 format with both 1024-
bit keys with SHA1 digest and 2048-bit keys with SHA-256 digest.
If the self-test fails, the module will not load and status will be returned. If the status is
STATUS_INVALID_IMAGE_HASH, then a self-test failed. Otherwise, STATUS_SUCCESS is returned.
9 Design Assurance
The secure installation, generation, and startup procedures of this cryptographic module are part of the
overall operating system secure installation, configuration, and startup procedures for Windows 10
operating system.
The Windows 10 operating system must be pre-installed on a computer by an OEM, installed by the
end-user, by an organization’s IT administrator, or updated from a previous Windows 10 version
downloaded from Windows Update.
An inspection of authenticity of the physical medium can be made by following the guidance at this
Microsoft web site: https://www.microsoft.com/en-us/howtotell/default.aspx
The installed version of Windows 10 OEs must be verified to match the version that was validated. See
Appendix A for details on how to do this.
For Windows Updates, the client only accepts binaries signed by Microsoft certificates. The Windows
Update client only accepts content whose SHA-2 hash matches the SHA-2 hash specified in the
metadata. All metadata communication is done over a Secure Sockets Layer (SSL) port. Using SSL
ensures that the client is communicating with the real server and so prevents a spoof server from
sending the client harmful requests. The version and digital signature of new cryptographic module
releases must be verified to match the version that was validated. See Appendix A for details on how to
do this.
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10 Mitigation of Other Attacks
The following table lists the mitigations of other attacks for this cryptographic module:
Algorithm Protected Against Mitigation
SHA1 Timing Analysis Attack Constant time implementation
Cache Attack Memory access pattern is independent of any confidential
data
SHA2 Timing Analysis Attack Constant time implementation
Cache Attack Memory access pattern is independent of any confidential
data
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11 Security Levels
The security level for each FIPS 140-2 security requirement is given in the following table.
Security Requirement Security Level
Cryptographic Module Specification 1
Cryptographic Module Ports and Interfaces 1
Roles, Services, and Authentication 1
Finite State Model 1
Physical Security NA
Operational Environment 1
Cryptographic Key Management 1
EMI/EMC 1
Self-Tests 1
Design Assurance 2
Mitigation of Other Attacks 1
12 Additional Details
For the latest information on Microsoft Windows, check out the Microsoft web site at:
https://www.microsoft.com/en-us/windows
For more information about FIPS 140 validations of Microsoft products, please see:
https://docs.microsoft.com/en-us/windows/security/threat-protection/fips-140-validation
Secure Kernel Code Integrity Security Policy Document
© 2018 Microsoft. All Rights Reserved Page 24 of 24
This Security Policy is non-proprietary and may be reproduced only in its original entirety (without revision).
13 Appendix A – How to Verify Windows Versions and Digital Signatures
13.1 How to Verify Windows Versions
The installed version of Windows 10 OEs must be verified to match the version that was validated using
the following method:
1. In the Search box type "cmd" and open the Command Prompt desktop app.
2. The command window will open.
3. At the prompt, enter "ver”.
4. The version information will be displayed in a format like this:
Microsoft Windows [Version 10.0.xxxxx]
If the version number reported by the utility matches the expected output, then the installed version
has been validated to be correct.
13.2 How to Verify Windows Digital Signatures
After performing a Windows Update that includes changes to a cryptographic module, the digital
signature and file version of the binary executable file must be verified. This is done like so:
1. Open a new window in Windows Explorer.
2. Type “C:\Windows\” in the file path field at the top of the window.
3. Type the cryptographic module binary executable file name (for example, “CNG.SYS”) in the
search field at the top right of the window, then press the Enter key.
4. The file will appear in the window.
5. Right click on the file’s icon.
6. Select Properties from the menu and the Properties window opens.
7. Select the Details tab.
8. Note the File version Property and its value, which has a number in this format: xx.x.xxxxx.xxxx.
9. If the file version number matches one of the version numbers that appear at the start of this
security policy document, then the version number has been verified.
10. Select the Digital Signatures tab.
11. In the Signature list, select the Microsoft Windows signer.
12. Click the Details button.
13. Under the Digital Signature Information, you should see: “This digital signature is OK.” If that
condition is true, then the digital signature has been verified.