3.1.11·high·Component: Access ControlWhat this control requires
This control mandates the automatic termination of user sessions based on organization-defined conditions or trigger events, such as inactivity or time-of-day restrictions. It ensures that user access to the system is appropriately terminated without affecting network connections, preventing unauthorized access after the session ends. This control supports the Session Management System capability within the Access Control (3.1) family.
In plain English
This control mandates the automatic termination of user sessions based on organization-defined conditions or trigger events, such as inactivity or time-of-day restrictions. In practice, this means you can prove you access management-level controls on a defined cadence.
Why it matters
DoD contractors and their subcontractors must implement all 100 SP 800-171 requirements to keep CUI handling contracts. Gaps are scored against the SPRS scoring methodology; below a 110-point starting score, each unmet requirement deducts points and a below-threshold score can disqualify a bid.
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 C3PAO conducting a CMMC Level 2 assessment uses NIST SP 800-171A objectives. They expect a System Security Plan (SSP), Plan of Action & Milestones (POA&M) for any gaps, and objective evidence (configurations, ticket records, training records) for every requirement.
Within Access Control, the assessor will trace your implementation back to the catalogue reference (Requirement 3.1.11) and look for objective evidence on the latest two assessment cycles.
How to implement
Network Security
AWS. VPC Flow Logs to S3, default-deny security groups, AWS Network Firewall for north-south, and Transit Gateway for hub-and-spoke segmentation.
Azure. NSGs with deny-by-default, Azure Firewall Premium with TLS inspection, Private Endpoints for PaaS, and Microsoft Defender for Cloud's secure score for drift.
GCP. VPC Service Controls perimeters around sensitive APIs, Cloud NGFW Enterprise for L7 inspection, Private Service Connect for managed services.
Operational checklist
- Access. Document the trigger, the owner and the cadence.
- Session. Document the trigger, the owner and the cadence.
- Access Control. Document the trigger, the owner and the cadence.
- Time. Document the trigger, the owner and the cadence.
- System. Document the trigger, the owner and the cadence.
- Scope: management, termination, inactivity, time, security, access control.
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: Session Termination.
Common pitfalls
- Default-allow egress rules; East-West traffic with no segmentation; jump hosts on the public internet with password auth.
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 800-53 Rev. 5 AC-6(3) — Network Access To Privileged Commands
- CIS Controls v8 6.7 — Centralize Access Control
- BSI C5:2020 PS-04 — Physical site access control
- ISO/IEC 27001:2022 A.5.2 — Information security roles and responsibilities
- SOC 2 (2017 TSC) CC6.1 — Logical Access Controls
Related controls in NIST SP 800-171 Rev. 3
- Requirement 3.1.6 — Least Privilege - Privileged Accounts
- Requirement 3.1.8 — Unsuccessful Logon Attempts
- Requirement 3.9.2 — Personnel Termination and Transfer
- Requirement 3.1.7 — Least Privilege - Privileged Functions
- Requirement 3.1.22 — Publicly Accessible Content
- Requirement 3.1.12 — Remote Access
References
- NIST Computer Security Resource Center — NIST SP 800-171 Rev. 3
- Catalogue identifier:
Requirement 3.1.11
Topics: identity accessidentity managementaccess reviewprivileged accessnetwork security