If your organization handles Controlled Unclassified Information (CUI) for the U.S. Department of Defense (DoD) or other federal agencies, complying with NIST SP 800-171 is a contractual necessity.
However, the bar has been raised with the release of Revision 3 in May 2024. The updated version includes more controls, clearer language, and formal third-party risk management obligations. Read on to learn what this means for contractors and vendors in the Defense Industrial Base (DIB) and how Safous can help you satisfy these updated requirements.
NIST SP 800-171 defines the cybersecurity requirements for protecting CUI in non-federal systems and organizations.
Highlights of Rev. 3 include:1
97 requirements across 17 control families, including Supply Chain Risk Management (SR), Planning (PL), and System & Services Acquisition (SA)
Organizationally defined parameters (ODPs) to help measure thresholds that make controls auditable
Alignment with NIST SP 800-53 for consistency with broader federal standards
Complying with this standard is mandatory for Federal Contractual Requirement under DFARS 252.204-7012,2 as well as aligning with CMMC 2.0 Level 2.3 Beyond regulatory compliance, implementing NIST's technical controls is a national security imperative, considering supply chain cyberattacks surged by 431% from 2021 to 2023.4
Rev. 3 introduced several updates that organizations should be aware of. Let's break them down below.
Supply Chain Risk Management (SR) is now a dedicated control family, which means organizations must assess vendor risk, monitor third-party access continuously, and track remediation efforts if issues arise.
Compliance is no longer a once-a-year audit. Instead, organizations must actively monitor both their own systems and their vendors to detect and address issues as they emerge.
Control requirements are now clearer and easier to interpret. They're also mapped directly to NIST SP 800-53 and to CMMC Level 2, making it easier to build a unified compliance program across multiple frameworks.
Auditors expect evidence – not just policies. Organizations must show that controls are enforced and actively monitored. This changes compliance from a document-based task to a system of active control and oversight.
NIST SP 800-171 Rev. 3 applies to any organization that stores, processes, or transmits CUI. This includes:
Federal contractors and their subcontractors
Vendors and suppliers in multi-tier supply chains
IT, cloud, and service providers that handle CUI environments
Research institutions working on federally funded projects
Essentially, if your company supports federal missions, you are expected to demonstrate a clear and verifiable security posture.
While complying with NIST SP 800-171 Rev. 3 takes time and planning, a structured approach can make the process more manageable. Here are some steps to help you get started:
Start with a full assessment of your current posture. Review your environment against all 97 controls to identify where gaps exist. This includes both technical and procedural requirements.
Once you know where you stand, develop a System Security Plan (SSP) and a Plan of Action and Milestones (POA&M). These documents show auditors how you plan to address any shortfalls and what your timeline looks like.
Next, focus on implementation. This includes setting up access controls, encryption, vendor management policies, and monitoring tools. It's important to apply these controls across your systems and your supply chain.
From there, move into continuous monitoring. Point-in-time assessments are no longer enough. You’ll need tools and workflows to detect drift, audit vendor sessions, and respond to changes in real time.
Finally, be prepared to prove compliance. That means having the logs, artifacts, and access records ready to show how your controls work in practice.
Policies without proof won’t satisfy auditors. Safous can help your organization deliver that proof by enforcing and monitoring even the most challenging NIST Rev. 3 technical controls. Here's how:
Ready to comply with Rev. 3? Keep these best practices in mind:
Define Scope: Clearly define your CUI scope across your IT systems, OT environments, and any IoT or connected assets that may touch sensitive data to ensure that nothing falls through the cracks.
Engage Leadership: Compliance isn't just an IT effort. It requires collaboration across departments and coordination with your vendors, so get everyone on the same page at the start of the project.
Prioritize Vendor Oversight: Many NIST technical controls now require you to assess and monitor third-party access on an ongoing basis, so make sure to prioritize vendor oversight early.
Adopt Continuous Monitoring: Since point-in-time audits are no longer sufficient to maintain compliance with NIST SP 800-171, consider investing in tools and processes for continuous monitoring. Set up workflows that track activity, flag anomalies, and ensure enforcement of key controls.
Train Your Workforce: The new Awareness & Training (AT) family formalizes the need for staff to understand their role in protecting CUI, so don’t overlook workforce training.
Document Everything: Auditors will ask for SSPs, POA&Ms, access logs, remediation records, and proof of enforcement. Make sure these materials are updated and accessible at all times.
Adopt Zero Trust Principles: Enforcing Zero Trust principles like least privilege access, continuous identity verification, and eliminating assumptions about trust based on network location can help you comply with NIST.
NIST SP 800-171 Rev. 3 sets a new baseline for protecting CUI. It moves compliance from a paperwork exercise to a control-driven discipline, requiring organizations to go beyond policy and show that controls are actively enforced.
Safous can help you meet these expectations with tools designed for both enforcement and evidence, including access governance, continuous monitoring, remediation tracking, and audit-ready reports. With Safous, complying with Rev. 3 becomes a strategic advantage that can help your business secure more contracts, reduce risk, and build trust.
Contact us today to schedule a demo and see how Safous can help you streamline NIST SP 800-171 Rev. 3 compliance.
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