NIST SP 800-53 Rev. 5 SR-6 — Supplier Assessments And Reviews

What this control requires

Conduct assessments and reviews of the supply chain risks associated with suppliers or contractors and the system, system component, or service they provide. This process includes evaluating security, supply chain risk management, foreign ownership control/influence (FOCI), and the supplier's ability to assess their own suppliers. Reviews may be conducted internally or by third parties using various sources such as documentation, controls, and intelligence. This control supports the Third-Party Evaluation capability within the Supply Chain Risk Management family.

In plain English

Conduct assessments and reviews of the supply chain risks associated with suppliers or contractors and the system, system component, or service they provide. In practice, this means you can prove you policy management-level controls on a defined cadence.

Why it matters

SP 800-53 is the catalogue every U.S. federal authorisation (FedRAMP, FISMA, CMMC) and most regulated industries point at. A missing control surfaces as a Plan of Action & Milestones (POA&M) item that an Authorizing Official must approve before the Authority To Operate is granted or renewed.

This control is rated high. Auditors expect a named owner, a remediation SLA, and a tooling artefact that evidences continuous operation.

What an auditor looks for

A 3PAO (FedRAMP) or Independent Assessor (NIST RMF) tests against NIST SP 800-53A assessment procedures. For each control they expect a documented implementation that addresses every assessment objective (Examine, Interview, Test) and an implementation summary in the System Security Plan.

Within Supply Chain Risk Management, the assessor will trace your implementation back to the catalogue reference (Control SR-6) and look for objective evidence on the latest two assessment cycles.

How to implement

Policy Management

Docs. Keep each policy in version-controlled Markdown alongside the code that implements it; ship a signed PDF snapshot at each annual review and link the SHA into the SoA.

Operational checklist

• Policy. Document the trigger, the owner and the cadence.
• Process. Document the trigger, the owner and the cadence.
• Security. Document the trigger, the owner and the cadence.
• Chain. Document the trigger, the owner and the cadence.
• System. Document the trigger, the owner and the cadence.
• Scope: management, reviews, system, service, controls, assessments, sources, capability.

Evidence to collect

• Vendor Risk Management. vendor_risk_management evidence
• Policy Document. A signed and version-controlled policy / standard / procedure document.

Third-party risk management evidence (assessments, contracts, due diligence) shows supplier oversight. Signed policy or standard documents the safeguard. Focus: Supplier Assessments And Reviews.

Common pitfalls

• Policies that no engineer has read; the version in Confluence drifts from the version that's actually being enforced.

How it maps to other frameworks

Computed from shared tags, control component and key-operation subjects — handy when you are reconciling controls across an audit.

• NIST SP 800-171 Rev. 3 3.16.3 — External System Services
• ISO/IEC 27001:2022 A.5.19 — Information security in supplier relationships

Related controls in NIST SP 800-53 Rev. 5

• Control RA-3(2) — Use Of All-Source Intelligence
• Control SR-6(1) — Testing And Analysis
• Control SR-3(1) — Diverse Supply Base
• Control SR-5(1) — Adequate Supply
• Control SR-4(4) — Supply Chain Integrity -- Pedigree
• Control SA-12(2) — Supplier Reviews

References

• NIST Computer Security Resource Center — NIST SP 800-53 Rev. 5
• Catalogue identifier: Control SR-6

Topics: governance riskvendor riskvendor managementsupply chain securitypolicy managementthird party monitoring