NIST SP 800-53 Rev. 5 IA-2(13) — Out-Of-Band Authentication

What this control requires

Out-of-Band Authentication control requires implementing out-of-band authentication using separate communication paths (e.g., mobile device verification) to authenticate users or devices, meeting organization-defined conditions. This mitigates man-in-the-middle attacks and enhances authentication assurance. This control supports the Out-of-Band Authentication System capability within the Identification and Authentication family.

In plain English

Out-of-Band Authentication control requires implementing out-of-band authentication using separate communication paths (e.g., mobile device verification) to authenticate users or devices, meeting organization-defined conditions. In practice, this means you can prove you security 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 Identification and Authentication, the assessor will trace your implementation back to the catalogue reference (Control IA-2(13)) 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.

Operational checklist

• Security. Document the trigger, the owner and the cadence.
• Separate. Document the trigger, the owner and the cadence.
• Device. Document the trigger, the owner and the cadence.
• Protection. Document the trigger, the owner and the cadence.
• Authenticate. Document the trigger, the owner and the cadence.
• Scope: management, conditions, authentication, organization, system, e, protection, identity.

Evidence to collect

• User Device Scan. MDM compliance state per user device (Intune / Jamf / Workspace ONE).

Endpoint compliance telemetry (Intune, Jamf) proves managed coverage. Focus: Out-Of-Band Authentication.

Common pitfalls

• Pilot MDM rollouts that quietly exclude executives or engineers; carving out the highest-risk users is the most common audit failure.

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 3.5.2 — Device Identification and Authentication

Related controls in NIST SP 800-53 Rev. 5

• Control IA-5(11) — Hardware Token-Based Authentication
• Control IA-3 — Device Identification And Authentication
• Control IA-3(1) — Cryptographic Bidirectional Authentication
• Control IA-3(2) — Cryptographic Bidirectional Network Authentication
• Control IA-6 — Authentication Feedback
• Control IA-12(6) — Accept Externally-Proofed Identities

References

• NIST Computer Security Resource Center — NIST SP 800-53 Rev. 5
• Catalogue identifier: Control IA-2(13)

Topics: endpoint securityendpoint protectionidentity management