SC.L2-3.13.16
Data at Rest
Source and approval
CMMC Assessment Guide — Level 2 · Revision 2.13
Publisher approved · Complete cited source edition 2026-10-31
Read the official guideSee SC.L2-3.13.16 in the reference catalog with its NIST cross-references
Official requirement
Protect the confidentiality of CUI at rest.
Assessment objectives
a. the confidentiality of CUI at rest is protected.
Implementation guidance
Editorial examples to help you plan. Adapt them to your environment; the official requirement and objectives remain authoritative.
In plain language
Protect the confidentiality of controlled information at rest.
Implementation example
Example from the source assessment guide (not a mandatory implementation): Your company has a policy stating CUI must be protected at rest and y ou work to enforce that policy. You research Full Disk Encryption (FDE) products that meet the FIPS encryption requirement. After testing, you deploy the encryption to all computers to protect CUI at rest [a]. Example 2 You have used encryption to protect the CUI on most of the computers at your company, but you have some devices that do not support encryption . You create a policy requiring these devices to be signed out when needed, stay in possession of the signer when checked out, and to be signed back in and locked up in a secured closet when the user is done with the device [a]. At the end of the day each Friday, you audit the sign- out sheet and make sure all devices are returned to the closet.
Evidence examples
Examples suggested by the source guide (not an exhaustive or mandatory checklist): System and communications protection policy; procedures addressing protection of information at rest; system security plan; system design documentation; list of information at rest requiring confidentiality protections; system configuration settings and associated documentation; cryptographic mechanisms and associated configuration documentation; other relevant documents or records
Common mistakes
Protecting transmitted data while leaving stored copies inadequately protected.