Manual access reviews break down when identities are created dynamically and change faster than the review cycle. Teams miss dormant credentials, orphaned accounts, and privilege creep. The result is a governance process that certifies access after the fact instead of preventing exposure in time.
Why Manual Reviews Break for Non-Human Identities
Manual access reviews assume a stable inventory, predictable ownership, and a review cadence that can keep pace with change. That assumption does not hold for NHIs, where service accounts, API keys, OAuth grants, and workload identities can be created, modified, and abandoned faster than a quarterly or monthly attestation cycle can detect. Current guidance from the OWASP Non-Human Identity Top 10 treats review gaps as a core exposure, not a paperwork problem.
NHI Management Group research shows how severe the underlying problem can be: Ultimate Guide to NHIs reports that 97% of NHIs carry excessive privileges and only 20% of organisations have formal offboarding and revocation processes for API keys. That means a manual review often certifies yesterday’s state while the actual access graph has already changed. Reviews also tend to focus on named owners rather than actual runtime usage, so dormant credentials, orphaned accounts, and third-party OAuth exposure slip through. In practice, many security teams discover NHI sprawl only after a breach, not through a successful review cycle.
What a Better Review Model Looks Like in Practice
For NHIs, the review process has to shift from periodic approval to continuous evidence. Instead of asking, “Should this identity keep access?” on a calendar, teams need to ask, “What did this identity actually do, when, and under whose change record?” That requires a current inventory, ownership metadata, workload context, secret age, last-use telemetry, and revocation workflows that are triggered automatically when an identity is stale or unassigned.
Practically, mature programs combine control-plane visibility with lifecycle controls. The NHI Lifecycle Management Guide is most useful when paired with live discovery from cloud logs, vaults, CI/CD systems, and IdP events. The control objective is not just to validate access, but to prove that access remains necessary. That is why standards-oriented guidance such as the OWASP Non-Human Identity Top 10 emphasizes credential hygiene, least privilege, and visibility over one-time certification.
- Use automated discovery to build the review population before human attestation starts.
- Attach each NHI to a business owner, system owner, and expiration date.
- Flag dormant, over-privileged, or unrotated credentials for immediate action rather than deferred approval.
- Revoke or scope down access when ownership is unclear or the workload has changed.
This guidance tends to break down in highly fragmented environments where NHIs are embedded in legacy scripts, unmanaged SaaS apps, and multi-team DevOps pipelines because there is no reliable system of record for who owns the identity or what “normal” use looks like.
Common Failure Modes and Edge Cases
Tighter review controls often increase operational overhead, so organisations have to balance assurance against the speed of delivery. That tradeoff becomes real when NHIs are short-lived, auto-generated, or multiplied across environments, because a review queue can become the bottleneck instead of the control.
One common edge case is third-party access via OAuth apps or delegated service connections, where the “owner” is a vendor integration rather than a named internal user. Another is ephemeral CI/CD identities, which may be valid only for minutes and are better governed through event-driven policy than manual attestation. NHI Management Group’s State of Non-Human Identity Security highlights the depth of the visibility gap, and the underlying issue is consistent with broader identity guidance in the OWASP Non-Human Identity Top 10: if access cannot be observed continuously, it cannot be reviewed reliably.
Current guidance suggests treating manual reviews as a backstop, not the primary control. They are most useful for exception handling, ownership disputes, and post-incident validation. They are weakest when identities are machine-created at scale, when privileges are inherited indirectly, or when revocation depends on ticket-driven cleanup. In those cases, organisations need lifecycle automation, expiry enforcement, and continuous entitlement monitoring rather than another checkbox review.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 address the attack and risk surface, while NIST CSF 2.0 and NIST AI RMF set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-01 | Manual reviews fail without accurate inventory and ownership for NHIs. |
| NIST CSF 2.0 | PR.AC-4 | Access entitlements must be managed and reviewed as part of least privilege. |
| NIST AI RMF | Governance must account for dynamic, system-driven identity behaviour. |
Use AI governance practices to maintain accountability, traceability, and lifecycle controls for automated identities.
Related resources from NHI Mgmt Group
Deepen Your Knowledge
Reviewed and updated by the NHIMG editorial team on June 24, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
