<?xml version="1.0" encoding="UTF-8"?><!--Serialized by the GTRI Trustmark Framework API, version: 1.4.74--><tf:TrustmarkDefinition xmlns:tf="https://trustmarkinitiative.org/specifications/trustmark-framework/1.4/schema/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ds="http://www.w3.org/2000/09/xmldsig#"><tf:Metadata><tf:Identifier>https://artifacts.trustmarkinitiative.org/lib/tds/iso-iec-27000-clock-synchronization/2022/</tf:Identifier><tf:Name>ISO/IEC 27000 Clock Synchronization</tf:Name><tf:Version>2022</tf:Version><tf:Description>Specifies requirements in accordance with the security and privacy controls specified by ISO/IEC Publication 27001:2022, related to clock synchronization.</tf:Description><tf:PublicationDateTime>2025-05-15T00:00:00.000Z</tf:PublicationDateTime><tf:TrustmarkDefiningOrganization><tf:Identifier>https://trustmarkinitiative.org/</tf:Identifier><tf:Name>TMI</tf:Name><tf:Contact><tf:Kind>PRIMARY</tf:Kind><tf:Responder></tf:Responder><tf:Email>help@trustmarkinitiative.org</tf:Email><tf:Telephone>555-555-5555</tf:Telephone><tf:WebsiteURL>https://trustmarkinitiative.org/</tf:WebsiteURL></tf:Contact></tf:TrustmarkDefiningOrganization><tf:TargetRecipientDescription>Organizations seeking to demonstrate compliance with organizational information security, cybersecurity, and privacy protection requirements specified in ISO/IEC Publication 27001:2022.</tf:TargetRecipientDescription><tf:LegalNotice>This artifact is published by the Georgia Tech Research Institute (GTRI) as part of the Trustmark Initiative. This artifact and the information contained herein is provided on an "AS IS" basis, and GTRI disclaims all warranties, express or implied, including but not limited to any warranty that the use of the information herein will not infringe any rights or any implied warranties or merchantability or fitness for a particular purpose. In addition, GTRI disclaims legal liability for any loss incurred as a result of the use or reliance on the document or the information contained herein.</tf:LegalNotice><tf:Keywords><tf:Keyword>ISO/IEC 27001</tf:Keyword><tf:Keyword>ISO 27001</tf:Keyword><tf:Keyword>Information Security</tf:Keyword><tf:Keyword>Information Security Management</tf:Keyword><tf:Keyword>Information Security Management Systems</tf:Keyword><tf:Keyword>Cybersecurity</tf:Keyword><tf:Keyword>Privacy</tf:Keyword><tf:Keyword>Privacy Protection</tf:Keyword><tf:Keyword>Clock Synchronization</tf:Keyword></tf:Keywords></tf:Metadata><tf:Sources><tf:Source tf:id="Source47862220"><tf:Identifier>27001</tf:Identifier><tf:Reference>ISO/IEC 27001-2022, Information security, cybersecurity and privacy protection -- Information security management systems -- Requirements. Published 2022. Available at &lt;a href="https://www.iso.org/standard/27001"&gt;https://www.iso.org/standard/27001&lt;/a&gt;.</tf:Reference></tf:Source><tf:Source tf:id="Source47862221"><tf:Identifier>27002</tf:Identifier><tf:Reference>ISO/IEC 27002-2022, Information security, cybersecurity and privacy protection -- Information security controls. Third edition. Published 2022. Available at &lt;a href="https://www.iso.org/standard/75652.html"&gt;https://www.iso.org/standard/75652.html&lt;/a&gt;.</tf:Reference></tf:Source></tf:Sources><tf:ConformanceCriteria><tf:ConformanceCriterion tf:id="criterion1"><tf:Number>1</tf:Number><tf:Name>Clock Synchronization</tf:Name><tf:Description>The clocks of information processing systems used by the organization shall be synchronized to approved time sources.</tf:Description><tf:Citation><tf:Source tf:ref="Source47862220" xsi:nil="true"></tf:Source><tf:Description><![CDATA[Annex A, Control 8.17]]></tf:Description></tf:Citation><tf:Citation><tf:Source tf:ref="Source47862221" xsi:nil="true"></tf:Source><tf:Description><![CDATA[Section 8.17]]></tf:Description></tf:Citation></tf:ConformanceCriterion></tf:ConformanceCriteria><tf:AssessmentSteps><tf:AssessmentStep tf:id="ClockSynchronization"><tf:Number>1</tf:Number><tf:Name>Clock Synchronization</tf:Name><tf:Description>Are the clocks of information processing systems used by the organization synchronized to approved time sources?</tf:Description><tf:ConformanceCriterion tf:ref="criterion1" xsi:nil="true"></tf:ConformanceCriterion><tf:Artifact><tf:Name>A1</tf:Name><tf:Description><![CDATA[Provide evidence (e.g. organizational policies, procedures, compliance/assessment reports, etc.) and supporting notes as appropriate to support the assessor's response to this assessment step.]]></tf:Description></tf:Artifact></tf:AssessmentStep></tf:AssessmentSteps><tf:IssuanceCriteria><![CDATA[yes(ALL)]]></tf:IssuanceCriteria></tf:TrustmarkDefinition>