---
title: "NIST 800-171 3.5.2 (IA.L2-3.5.2): Authentication"
description: "NIST SP 800-171 3.5.2 Authentication: 5 SPRS points, not allowed on a CMMC POA&M. The text, what assessors check and the evidence."
url: https://policycortex.com/nist-800-171/identification-and-authentication/3.5.2
sealed: 2026-11-11
amended: 2026-11-11
register: nist-800-171/identification-and-authentication/3.5.2
records: 7
digest: sha3:04a32971fa718332c77830c5de9577f47161e7c69763fd674f572cb0b605d813
---

# NIST 800-171 3.5.2 (IA.L2-3.5.2): Authentication

NIST 800-171 / Identification and Authentication / 3.5.2

"Authenticate (or verify) the identities of users, processes, or devices, as a prerequisite to allowing access to organizational systems." ([NIST SP 800-171 Rev. 2, requirement 3.5.2](https://doi.org/10.6028/NIST.SP.800-171r2))

CMMC Level 2 practice IA.L2-3.5.2.

## What 3.5.2 means in practice

Identity has to be proven before access is granted, for people, for processes and for devices. Passwords with multifactor authentication for people, certificates or managed credentials for services, and device certificates or compliance checks for machines are the usual means; stale or never-rotated credentials weaken every one of them.

## SPRS points and the CMMC POA&M

- **CMMC Level 2 practice**: IA.L2-3.5.2
- **SPRS points**: 5 points. When it is not met, the DoD Assessment Methodology subtracts 5 from the score of 110.
- **CMMC POA&M**: Not allowed. It is worth 5 points, and 32 CFR 170.21(a)(2)(ii) admits only requirements worth 1 point, with one exception: 3.13.11 when encryption is used but not FIPS validated.

Sources: [NIST SP 800-171 DoD Assessment Methodology, version 1.2.1 (June 24, 2020), Annex A](https://www.acq.osd.mil/asda/dpc/cp/cyber/docs/safeguarding/NIST-SP-800-171-Assessment-Methodology-Version-1.2.1-6.24.2020.pdf); [32 CFR 170.21, Plan of Action and Milestones requirements](https://www.ecfr.gov/current/title-32/section-170.21).

## What an assessor checks for 3.5.2

NIST SP 800-171A gives 3 determination statements for 3.5.2, each found satisfied or other than satisfied. Determine if:

- 3.5.2[a] the identity of each user is authenticated or verified as a prerequisite to system access.
- 3.5.2[b] the identity of each process acting on behalf of a user is authenticated or verified as a prerequisite to system access.
- 3.5.2[c] the identity of each device accessing or connecting to the system is authenticated or verified as a prerequisite to system access.

[NIST SP 800-171A (June 2018), assessment objectives for 3.5.2](https://doi.org/10.6028/NIST.SP.800-171A)

## Evidence that shows 3.5.2 is met

- Authentication settings for each access path: identity provider, VPN, servers and applications.
- How service accounts and processes authenticate, such as certificates, managed identities or rotated keys.
- Device authentication settings, such as certificate-based network access or device compliance checks.

## How PolicyCortex gathers the evidence

PolicyCortex reads this evidence with the collectors below, read only, and grades 3.5.2 from it. Each line says what the product checks.

- **AWS: IAM.** Checks that active IAM access keys are rotated within 90 days, flags credentials unused for 90 days, and checks that the root account has no access keys.

## Related pages

- **Calculator**: [SPRS score calculator: mark 3.5.2 and the other 109 requirements and see the score.](https://policycortex.com/sprs-score-calculator#family-IA)
- **Sample package**: [Sample package: an SSP, a POA&M and an evidence chain the product generated from demonstration data.](https://policycortex.com/sample-package)
- **Family**: [All 11 Identification and Authentication requirements (3.5).](https://policycortex.com/nist-800-171/identification-and-authentication)
- **Previous**: [3.5.1: Identification](https://policycortex.com/nist-800-171/identification-and-authentication/3.5.1)
- **Next**: [3.5.3: Multifactor Authentication](https://policycortex.com/nist-800-171/identification-and-authentication/3.5.3)
- **All requirements**: [All 110 NIST SP 800-171 requirements, by family.](https://policycortex.com/nist-800-171)

Meet the requirement once. Keep the evidence current. [Request Access](https://app.policycortex.com/auth?mode=request-access) · [Book a call](https://policycortex.com/book)

## Register colophon

| Seq | Label | SHA3-256 | Prev |
|---|---|---|---|
| REC 0000 | REQUIREMENT | 7915bbf2a654 | 8057f8c3ad9b |
| REC 0001 | MEANING | 14de6a7ea3e1 | 7915bbf2a654 |
| REC 0002 | POINTS AND POA&M | c7f70c8c60f3 | 14de6a7ea3e1 |
| REC 0003 | ASSESSMENT OBJECTIVES | 57785fdc0477 | c7f70c8c60f3 |
| REC 0004 | EVIDENCE | c7022088b16f | 57785fdc0477 |
| REC 0005 | COLLECTORS | 9680797baaee | c7022088b16f |
| REC 0006 | RELATED | 04a32971fa71 | 9680797baaee |

Head sha3:04a32971fa718332c77830c5de9577f47161e7c69763fd674f572cb0b605d813. Each digest is SHA3-256 over the previous digest, the register key, the record label, and the record copy; a second party can recompute it from this document.