# IA-05 (02) Public Key-based Authentication — NIST 800-53 Rev5 control

> FedRAMP Consolidated Rules for 2026 v2026.07.14.01 · updated 2026-07-14
> Canonical page: /control/ia-5.2

Canonical id: `ia-5.2` · family `IA`

> (a) For public key-based authentication: (1) Enforce authorized access to the corresponding private key; and (2) Map the authenticated identity to the account of the individual or group; and (b) When public key infrastructure (PKI) is used: (1) Validate certificates by constructing and verifying a certification path to an accepted trust anchor, including checking certificate status information; and (2) Implement a local cache of revocation data to support path discovery and validation.

_Control title and statement: NIST SP 800-53 Rev5 catalog (the pinned commit is in `/api` under `control_text`). The FedRAMP rules reference these controls by id only; everything below is what FedRAMP says about this id._

## Rev5 baseline membership

- certification class C
- certification class D

## Key Security Indicators that reach it

- `KSI-IAM-APM` — Adopting Passwordless Methods (Identity and Access Management)
  Secure passwordless methods are used for user authentication and authorization when feasible, otherwise strong passwords with phishing-resistant MFA is used.
- `KSI-IAM-ELP` — Ensuring Least Privilege (Identity and Access Management)
  Identity and access management measures are used and persistently reviewed to ensure each user or device can only access the resources they need.
- `KSI-IAM-SNU` — Securing Non-User Authentication (Identity and Access Management)
  Appropriately secure authentication methods are used and persistently reviewed for non-user accounts and services.
- `KSI-SVC-ASM` — Automating Secret Management (Service Configuration)
  Management, protection, and regular rotation of digital keys, certificates, and other secrets is automated and persistently reviewed.

## FedRAMP guidance

_No FedRAMP-specific guidance attaches to this control._