SR-8 Notification agreements
What the standard requires
Establish agreements and procedures with entities involved in the supply chain for the system, system component, or system service for the [notification of supply chain compromises | [results of assessments or audits] ].
Quoted verbatim from NIST SP 800-53 Rev 5 (OSCAL catalog), which is in the public domain.
Cross-framework mappings
No cross-framework mapping is seeded for this control. That is stated rather than filled in: a mapping nobody authored is worse than a gap you can see.
Track SR-8 with evidence behind it
In CMDash this control is a row with an owner, a status, uploaded evidence kept with its full history, and an export an assessor can read.