AC-3(4) - Access Enforcement | Discretionary Access Control

Enforce [Assignment: organization-defined discretionary access control policy] over the set of covered subjects and objects specified in the policy, and where the policy specifies that a subject that has been granted access to information can do one or more of the following: (a) Pass the information to any other subjects or objects; (b) Grant its privileges to other subjects; (c) Change security attributes on subjects, objects, the system, or the system’s components; (d) Choose the security attributes to be associated with newly created or revised objects; or (e) Change the rules governing access control.


ID: AC-3(4)
Enhancement of : AC-3

Space Segment Guidance

Where discretionary access controls are used (commonly for payload data stores or file-based tasking), consider how owner-managed permissions coexist with mission safety and command authorization. Useful practices include short-lived, purpose-specific grants tied to execution windows or end-of-pass; mode-aware constraints that prevent DAC from expanding privileges during hazardous states; and clear provenance so permission changes, content sources, and outcomes can be reconstructed from audit and telemetry. Because revocation opportunities are limited on-orbit, automatic expiration and conservative defaults help reduce drift, while resilience to resets and radiation effects (e.g., integrity checks on permission metadata) maintains consistency between ground intent and on-board state.