Windows Server 2025 systems requiring data-at-rest protections must employ cryptographic mechanisms to prevent unauthorized disclosure and modification of the information at rest.

This requirement addresses protection of user-generated data as well as operating system-specific configuration data. Organizations may choose to employ different mechanisms to achieve confidentiality and integrity protections, as appropriate, in accordance with the security category and/or classification of the information.

Selection of a cryptographic mechanism is based on the need to protect the integrity of organizational information. The strength of the mechanism is commensurate with the security category and/or classification of the information. Organizations have the flexibility to either encrypt all information on storage devices (i.e., full disk encryption) or encrypt specific data structures (e.g., files, records, or fields).

Satisfies: SRG-OS-000185-GPOS-00079, SRG-OS-000404-GPOS-00183, SRG-OS-000405-GPOS-00184

Note: If there is a documented and approved reason to omit data-at-rest encryption at the operating system level, such as encryption provided by a hypervisor or a disk storage array in a virtualized environment, this requirement is not applicable.

Verify systems that require additional protections due to factors such as inadequate physical protection or sensitivity of the data employ encryption to protect the confidentiality and integrity of all information at rest.

If there is no evidence that persistent user-generated data and operating system-specific configuration data are encrypted, this is a finding.

Configure systems that require data-at-rest protections to employ encryption to protect the confidentiality and integrity of all persistent user-generated data and operating system-specific configuration data.

The encryption method implemented must use FIPS-compliant algorithms.