If you’ve been wrestling with how to scope systems that only touch encrypted CUI, the DoD just handed you a gift. Their January 2026 FAQ update directly addresses one of the most expensive questions in CMMC Level 2 preparation: Can systems that only process encrypted CUI be excluded from your full assessment boundary?
The answer fundamentally changes how you approach scoping.
Why This Matters Now
Before this guidance, the conservative approach was to treat any system touching CUI, encrypted or not, as a full CUI Asset requiring all 110 CMMC Level 2 practices. That meant your file transfer servers, backup systems, and transit-only infrastructure all needed the complete NIST 800-171 treatment. For many contractors, that turned a manageable 20-system boundary into a 100-system nightmare.
The new FAQ clarifies that systems processing only encrypted CUI can potentially be categorized as Specialized Assets or even Security Protection Assets rather than CUI Assets, dramatically reducing the controls required.
The Practical Impact
Here’s what changes:
Systems that only store or transmit encrypted CUI may now require just the subset of practices from Table 3 (Specialized Assets) instead of all 110 practices. Think backup servers that only hold encrypted archives or file transfer systems that never decrypt data in transit.
Key requirement: The encryption must meet FIPS 140-2 validated standards (addressing practice 3.13.11), and the system must never have access to the decryption keys. If your backup system can decrypt the data it stores, it’s still a full CUI Asset.
This aligns with the underlying logic of NIST 800-171: protecting CUI confidentiality. If a system literally cannot access the plaintext CUI, the full control set becomes overkill.
What You Need to Do
1. Audit your current scoping artifacts. Every system in your assessment boundary needs re-evaluation against this new guidance. Document which systems only handle encrypted CUI and never possess decryption capability.
2. Update your network diagrams. Clearly distinguish between systems that process encrypted vs. unencrypted CUI. Your assessor will need this documentation to justify the reduced control set.
3. Validate your encryption. This only works with FIPS 140-2 validated encryption. If you’re using anything else, these systems remain full CUI Assets.
4. Document the key management. You must prove these systems cannot decrypt the CUI they handle. Show where keys are stored and which systems have access.
The Bottom Line
This guidance can cut your remediation costs by 30-50% if you have significant encrypted data flows. But it requires precise documentation and clear architectural boundaries. The assessment objective hasn’t changed, you still need to protect CUI. The DoD just acknowledged that encryption, properly implemented, is protection.
Miss this distinction in your scoping, and you’ll spend months implementing controls on systems that don’t need them. Get it right, and you’ve just made CMMC Level 2 achievable for your actual CUI environment, not your entire infrastructure.
This is the kind of change that shows up in assessments. If your SSP doesn’t reflect it yet, now is the time. Contact us to update your scoping before you waste budget on unnecessary remediation.