What evidence do auditors commonly ask for on SA-9 External System Services?

Inventory of external services; Agreements defining security roles and responsibilities; Monitoring and assessment evidence; Exit and transition arrangements.

What is the most common gap auditors find on SA-9?

responsibilities assumed rather than defined

NIST SP 800-161 Rev 1 (supply chain) · C-SCRM Family: System and Services Acquisition

`SA-9` External System Services

Governs external service providers across their life cycle, including the security roles each party holds.

Source: NIST SP 800-161 Rev 1 (supply chain), SA-9. The statement above is our statement of the clause, read from the published text and cited so you can check it against the official text, not the instrument verbatim. Open NIST SP 800-161 Rev 1 (supply chain) in the compliance library.

artefacts

held by a system

at each review

hard

to go live

Policy repository / GRC workspace

where the evidence lives

teal = a system already holds it · olive = produced at each review. To go live: easy when half or more of the artefacts are already held by a system, moderate from a quarter to a half, hard below a quarter.

These are the artefacts auditors commonly ask for on this requirement, our guidance rather than text from the standard. Your assessor decides what is sufficient in your context, and asks for samples across the period when a report covers one.

system holds itEvidence a system already holds

none for this control

periodic reviewEvidence produced at each review

Monitoring and assessment evidence · SIEM / log platform

governing documentDocuments that govern the control

Inventory of external services · Policy repository / GRC workspace
Agreements defining security roles and responsibilities · Policy repository / GRC workspace
Exit and transition arrangements · Document repository

First move

No system holds this evidence for you: it is people and documents. Reminders and routing to the owner still save time. Put the document under version control with an owner and review date, and log each review as a record with reviewer and date.

Common gaps auditors find

responsibilities assumed rather than defined
no exit plan so provider change is impossible

Do this for your whole sheet

Paste the rows you run your controls from and get this mapping for every control at once, with the periodic-review ones flagged and a first move per row. No account for the first run.

Build my evidence sheet

SA-8 Security and Privacy Engineering Principles · SA-10 Developer Configuration Management