What this requirement asks
Implement cryptographic mechanisms to prevent unauthorized disclosure of CUI during transmission unless otherwise protected by alternative physical safeguards.
This is a CMMC Level 2 requirement in the System & Communications Protection family, drawn from NIST SP 800-171 Rev. 2. An assessor evaluates it objective by objective — every objective below must be supported by evidence, not just described in a policy.
Assessment objectives (3)
- 3.13.8[a] — cryptographic mechanisms intended to prevent unauthorized disclosure of CUI are identified
- 3.13.8[b] — alternative physical safeguards intended to prevent unauthorized disclosure of CUI are identified
- 3.13.8[c] — either cryptographic mechanisms or alternative physical safeguards are implemented to prevent unauthorized disclosure of CUI during transmission
What an assessor examines
Examine:
- System and communications protection policy
- procedures addressing transmission confidentiality and integrity
- system security plan
- system design documentation
- system configuration settings and associated documentation
- system audit logs and records
- other relevant documents or records
Interview:
- System or network administrators
- personnel with information security responsibilities
- system developer
Test:
- Cryptographic mechanisms or mechanisms supporting or implementing transmission confidentiality
- organizational processes for defining and implementing alternative physical safeguards
Evidence that defends it
Show key rotation/storage controls
Check your readiness
Score this requirement against your own environment with the Level 2 self-assessment checklist, or estimate your SPRS score with the free CMMC compliance tool. Self-reported answers are planning signals only — they do not establish a verified or assessor-accepted result.