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Search Search CSRC MENU Search Search Projects Publications Expand or Collapse Drafts for Public Comment All Public Drafts Final Pubs FIPS (standards) Special Publications (SP s ) IR (interagency/internal reports) CSWP (cybersecurity white papers) ITL Bulletins Project Descriptions Journal Articles Conference Papers Books Topics Expand or Collapse Security & Privacy Applications Technologies Sectors Laws & Regulations Activities & Products News & Updates Events Glossary About CSRC Expand or Collapse Computer Security Division Cryptographic Technology Software Security Group Hardware Security Group Security Engineering and Risk Management Applied Cybersecurity Division Cybersecurity and Privacy Applications National Cybersecurity Center of Excellence (NCCoE) National Initiative for Cybersecurity Education (NICE) Contact Us Information Technology Laboratory Computer Security Resource Center Publications NIST SP 800-172 Rev. 3 Enhanced Security Requirements for Protecting Controlled Unclassified Information Share to Facebook Share to X Share to LinkedIn Share ia Email Documentation Topics Date Published: May 2026 Supersedes: SP 800-172 (02/02/2021) Planning Note ( 05/13/2026 ): The enhanced security requirements in SP 800-172r3 are available in multiple data formats. The PDF of SP 800-172r3 is the authoritative source of the enhanced security requirements. If there are any discrepancies noted in the content between the CPRT dataset , OSCAL dataset , and the SP 800-172r3 PDF , please contact [email protected] and refer to the PDF as the normative source. Author(s) Victoria Pillitteri (NIST) , Ron Ross (NIST) Abstract The protection of Controlled Unclassified Information (CUI) resident in nonfederal systems and organizations is of paramount importance to federal agencies and can directly impact the ability of the Federal Government to successfully conduct its essential missions and functions. This publication provides federal agencies with a set of recommended enhanced security requirements for providing additional protection to the confidentiality, integrity, and availability of CUI when it is resident in a nonfederal system and organization and associated with a critical program or high value asset (HVA). It is designed as a supplement to NIST Special Publication (SP) 800-171 to protect against advanced persistent threats (APTs). The security requirements apply to the components of nonfederal systems that process, store, or transmit CUI or that provide protection for such components only when selected and required by federal agencies to manage risks to CUI. The enhanced security requirements are intended for use by federal agencies in contractual vehicles or other agreements established between those agencies and nonfederal organizations. There is no expectation that all of the enhanced security requirements will be selected by federal agencies. The decision to select a particular set of enhanced security requirements will be based on the mission and business needs of federal agencies and guided and informed by agencies’ ongoing risk assessments. The protection of Controlled Unclassified Information (CUI) resident in nonfederal systems and organizations is of paramount importance to federal agencies and can directly impact the ability of the Federal Government to successfully conduct its essential missions and functions. This publication... See full abstract The protection of Controlled Unclassified Information (CUI) resident in nonfederal systems and organizations is of paramount importance to federal agencies and can directly impact the ability of the Federal Government to successfully conduct its essential missions and functions. This publication provides federal agencies with a set of recommended enhanced security requirements for providing additional protection to the confidentiality, integrity, and availability of CUI when it is resident in a nonfederal system and organization and associated with a critical program or high value asset (HVA). It is designed as a supplement to NIST Special Publication (SP) 800-171 to protect against advanced persistent threats (APTs). The security requirements apply to the components of nonfederal systems that process, store, or transmit CUI or that provide protection for such components only when selected and required by federal agencies to manage risks to CUI. The enhanced security requirements are intended for use by federal agencies in contractual vehicles or other agreements established between those agencies and nonfederal organizations. There is no expectation that all of the enhanced security requirements will be selected by federal agencies. The decision to select a particular set of enhanced security requirements will be based on the mission and business needs of federal agencies and guided and informed by agencies’ ongoing risk assessments. Hide full abstract Keywords advanced persistent threat ; contractor systems ; controlled unclassified information ; CUI registry ; enhanced security requirement ; Executive Order 13556 ; FISMA ; NIST Special Publication 800-172 ; NIST Special Publication 800-53 ; nonfederal organizations ; nonfederal systems ; security assessment ; security control ; security requirement Control Families None selected Documentation Publication: https://doi.org/10.6028/NIST.SP.800-172r3 Download URL Supplemental Material: Enhanced Security Requirements Overlay SP 800-172 to SP 800-172r3 Change Analysis 172r3 dataset on CPRT 172r3 dataset in OSCAL Publication Parts: SP 800-172A Rev. 3 Related NIST Publications: SP 800-171A Rev. 3 SP 800-171 Rev. 3 Document History: 11/13/24: SP 800-172 Rev. 3 (Draft) 09/29/25: SP 800-172 Rev. 3 (Draft) 05/13/26: SP 800-172 Rev. 3 (Final) Topics Security and Privacy advanced persistent threats , continuous monitoring , planning , risk assessment Laws and Regulations Federal Information Security Modernization Act , OMB Circular A-130 HEADQUARTERS 100 Bureau Drive Gaithersburg, MD 20899 X (link is external) facebook (link is external) linkedin (link is external) instagram (link is external) youtube (link is external) rss govdelivery (link is external) Want updates about CSRC and our publications? 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