NIST SP 800-53 Rev. 5 SA-9(6) — Organization-Controlled Cryptographic Keys

What this control requires

Maintain exclusive control of cryptographic keys for encrypted data stored or transmitted through external systems. Implement encryption and decryption either internally or via components that restrict key access solely to the organization. This control supports the Exclusive Key Management Protocol capability within the System and Services Acquisition family.

In plain English

Maintain exclusive control of cryptographic keys for encrypted data stored or transmitted through external systems. In practice, this means you can prove you access 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 System and Services Acquisition, the assessor will trace your implementation back to the catalogue reference (Control SA-9(6)) and look for objective evidence on the latest two assessment cycles.

How to implement

1. Write a short policy stating intent, scope and named owner.
2. Encode it as a platform guardrail — SCP, Azure Policy initiative, Organisation Policy, or repository policy.
3. Wire a monitoring signal that catches drift (CSPM rule, SIEM rule, scheduled query, Workspace alert) and ticket it.
4. Review on a documented cadence and capture the review in the risk register or compliance tracker.

Operational checklist

• Access. Document the trigger, the owner and the cadence.
• Restrict. Document the trigger, the owner and the cadence.
• Data. Document the trigger, the owner and the cadence.
• Review. Document the trigger, the owner and the cadence.
• Protection. Document the trigger, the owner and the cadence.
• Scope: management, cryptographic keys, organization, system, encryption, external systems, protection, identity.

Evidence to collect

• Identity Scan. IAM / IdP exports — Entra ID, Okta, IAM Identity Center, Workspace directory — showing accounts, roles, MFA state and last sign-in.

Identity analytics (Okta, SailPoint, Access Analyzer) demonstrates least-privilege. Focus: Organization-Controlled Cryptographic Keys.

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 3.15.2 — System Security Plan
• SOC 2 (2017 TSC) P5.1 — Data Subject Access to Personal Information
• CIS Controls v8 9.2 — Use DNS Filtering Services
• BSI C5:2020 IDM-08 — Confidentiality of authentication information

Related controls in NIST SP 800-53 Rev. 5

• Control SC-12(1) — Availability
• Control MP-5(1) — Protection Outside Of Controlled Areas
• Control SA-8(9) — Trusted Components
• Control SA-19(3) — Component Disposal
• Control MP-4(1) — Cryptographic Protection
• Control MP-5(4) — Cryptographic Protection

References

• NIST Computer Security Resource Center — NIST SP 800-53 Rev. 5
• Catalogue identifier: Control SA-9(6)

Topics: identity accessdata protectionidentity managementaccess reviewprivileged accessencryption at rest