NIST SP 800-53 Rev. 5 SA-8(6) — Minimized Sharing

What this control requires

Apply the principle of minimized sharing to restrict resource sharing between system components unless explicitly required. Use design techniques like virtualization and encapsulation to reduce risks of unauthorized access or data leakage. This control supports the Sharing Minimization Layer capability within the System and Services Acquisition family.

In plain English

Apply the principle of minimized sharing to restrict resource sharing between system components unless explicitly required. 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.

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-8(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.
• Unauthorized. Document the trigger, the owner and the cadence.
• Scope: management, system, virtualization, identity, review, components, services, capability.

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: Minimized Sharing.

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
• CIS Controls v8 9.2 — Use DNS Filtering Services
• ISO/IEC 27001:2022 A.8.23 — Web filtering
• ISO/IEC 27701:2025 A.3.8 — Identity management

Related controls in NIST SP 800-53 Rev. 5

• Control SA-8(9) — Trusted Components
• Control SA-19(3) — Component Disposal
• Control SA-8(14) — Least Privilege
• Control SA-12(14) — Identity And Traceability
• Control SA-8(22) — Accountability And Traceability
• Control SA-4(10) — Use Of Approved Piv Products

References

• NIST Computer Security Resource Center — NIST SP 800-53 Rev. 5
• Catalogue identifier: Control SA-8(6)

Topics: identity accessidentity managementaccess reviewprivileged accessdata loss prevention