# NIST SP 800-171 Rev. 3 3.1.10 — Device Lock - Source: https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-1-10-device-lock - Section: [Compliance](https://support.icompaas.com/compliance) › [NIST SP 800-171 Rev. 3 Requirements](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3) › Access Control — §3.1 - Last updated: 2026-06-05 - Publisher: iCompaas, Inc. (https://www.icompaas.com) **NIST SP 800-171 Rev. 3**·Requirement `3.1.10`·medium·Component: **Access Control** ## What this control requires > This control ensures that access to the system is prevented by initiating a device lock after a specified period of inactivity or requiring the user to lock the device before leaving it unattended. The lock conceals any previously visible information and retains access until the user reestablishes authentication through established identification procedures. This control supports the Device Lock Mechanism capability within the Access Control (3.1) family. > > — NIST SP 800-171 Rev. 3, Requirement 3.1.10 ### In plain English This control ensures that access to the system is prevented by initiating a device lock after a specified period of inactivity or requiring the user to lock the device before leaving it unattended. 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. ## 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 3.1.10) and look for objective evidence on the latest two assessment cycles. ## How to implement #### Endpoint Protection **MDM.** Make MDM enrollment a hard gate for device access (Intune compliance + Conditional Access, or Jamf + Okta device trust). Unmanaged devices simply don't get a session token. **EDR.** Deploy CrowdStrike / SentinelOne / Defender for Endpoint to every server and laptop; alert on any host that stops sending telemetry for >24h. #### 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 - **Access.** Document the trigger, the owner and the cadence. - **Information.** Document the trigger, the owner and the cadence. - **Device.** Document the trigger, the owner and the cadence. - **Access Control.** Document the trigger, the owner and the cadence. - **Protection.** Document the trigger, the owner and the cadence. - **Scope:** management, lock, inactivity, authentication, access control, protection, procedures. ## Evidence to collect - **Policy Document.** A signed and version-controlled policy / standard / procedure document. - **Infra Scan.** Continuous infrastructure-posture telemetry — AWS Config, Azure Policy compliance, GCP Organisation Policy, Wiz / Prisma findings. Signed policy or standard documents the safeguard. Focus: Device Lock. ## Common pitfalls - Pilot MDM rollouts that quietly exclude executives or engineers; carving out the highest-risk users is the most common audit failure. - 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 800-53 Rev. 5 AC-11** — Device Lock](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/ac-11-device-lock) - [**ISO/IEC 27001:2022 A.5.17** — Authentication information](https://support.icompaas.com/compliance/iso-27001-2022/a-5-17-authentication-information) - [**HIPAA (45 CFR Part 164) 164.310(a)(2)(iii)** — Facility Access Controls - Access Control and Validation Procedures](https://support.icompaas.com/compliance/hipaa/164-310-a-2-iii-facility-access-controls-access-control-and-validation-procedures) - [**CIS Controls v8 6.8** — Define and Maintain Role-Based Access Control](https://support.icompaas.com/compliance/cis-controls-v8/6-8-define-and-maintain-role-based-access-control) ## Related controls in NIST SP 800-171 Rev. 3 - [**Requirement 3.1.5** — Least Privilege](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-1-5-least-privilege) - [**Requirement 3.1.20** — Use of External Systems](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-1-20-use-of-external-systems) - [**Requirement 3.1.2** — Access Enforcement](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-1-2-access-enforcement) - [**Requirement 3.1.9** — System Use Notification](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-1-9-system-use-notification) - [**Requirement 3.1.11** — Session Termination](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-1-11-session-termination) - [**Requirement 3.1.22** — Publicly Accessible Content](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-1-22-publicly-accessible-content) ## References - [NIST Computer Security Resource Center — NIST SP 800-171 Rev. 3](https://csrc.nist.gov/pubs/sp/800/171/r3/final) - Catalogue identifier: `Requirement 3.1.10` Topics: governance riskendpoint protectionidentity managementpolicy management ## Related compliance guidance - [NIST SP 800-171 and CMMC: a practical guide to protecting CUI in the cloud](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3): Start with the full NIST SP 800-171 implementation guide — scope, roadmap, evidence and how the assessment runs. - [NIST SP 800-53 Rev. 5: a practical implementation guide for cloud teams](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5): The catalogue 800-171 is tailored from, and the basis of the FedRAMP Moderate baseline your cloud providers must meet for CUI. - [ISO/IEC 27001:2022 compliance: a practical implementation guide](https://support.icompaas.com/compliance/iso-27001-2022): If commercial customers ask for a certificate as well, most 800-171 controls can be evidenced once and mapped to Annex A.