Because approval is the least disruptive choice when the reviewer lacks confidence. If the interface only shows an entitlement and no usage, purpose, or risk signal, revocation feels like a guess. The process therefore rewards caution in name only and defaults to preserving access rather than challenging it.
Why This Matters for Security Teams
Access reviews are supposed to remove stale or unnecessary privileges, but they often become a retention exercise when reviewers cannot see whether access is actually being used. Without usage history, business context, or risk signals, the safe human choice is to preserve the entitlement and avoid interrupting a system that may still depend on it. That is especially dangerous for NHIs, where access is commonly long-lived, over-scoped, and poorly documented.
This is not a niche hygiene issue. NHI Mgmt Group notes that Ultimate Guide to NHIs reports 97% of NHIs carry excessive privileges, and only 20% of organisations have formal offboarding and revocation processes for API keys. When those conditions meet an approval workflow that lacks evidence, reviewers are effectively asked to guess what to remove. In practice, many security teams discover excessive access only after a service account is abused, rather than through a deliberate review outcome.
The deeper issue is that access reviews are often built around entitlement ownership, not entitlement necessity. That makes sense for stable human roles, but it breaks down when secrets, service accounts, and automation identities accumulate permissions faster than anyone can validate them. OWASP’s OWASP Non-Human Identity Top 10 treats overprivilege and lifecycle failure as core risks, not edge cases.
How It Works in Practice
The review outcome is usually shaped by the quality of evidence presented. When a reviewer sees only “has access” and “approve or remove,” the workflow creates false certainty. If the reviewer cannot tell whether an API key was used yesterday, whether a service account supports a production pipeline, or whether the privilege is redundant because another control now handles the task, revocation becomes a speculative action.
Better practice is to make the review decision evidence-based. That means pairing entitlements with signals such as last use, call frequency, owning application, environment, ticket history, and the control that originally justified the permission. For NHIs, this also means separating human approval from machine-operational reality: a dormant secret may still be embedded in code, while an active credential may be used only during month-end processing or incident response.
- Show actual usage, not only entitlement membership.
- Map each access grant to a business purpose or system dependency.
- Flag excessive privilege, long TTLs, and orphaned ownership before review.
- Use revocation paths that can safely test, stage, or roll back removal.
That operational model aligns with the NHI Lifecycle Management Guide, which emphasises that discovery, ownership, rotation, and offboarding need to be continuous rather than periodic. It also fits the intent of the OWASP Non-Human Identity Top 10, where lifecycle gaps and overprivilege are treated as systemic failure modes. The practical shift is to treat access review as a decision-support process, not a checkbox.
Teams that add telemetry, asset ownership, and purpose binding usually see far fewer “approve by default” outcomes because reviewers can distinguish dead access from still-critical automation. These controls tend to break down in environments with shared service accounts and undocumented code-level secrets because no one can prove which workload will fail if the entitlement is removed.
Common Variations and Edge Cases
Tighter review criteria often increase operational overhead, requiring organisations to balance revocation confidence against the cost of interrupting legitimate automation. That tradeoff is real, especially where legacy systems, shared credentials, or vendor-managed integrations make clean ownership impossible.
Current guidance suggests a tiered model rather than a single approval rule. High-risk access should require evidence of use and explicit business justification, while low-risk, low-impact entitlements may be auto-expired if they are idle beyond a defined threshold. For NHIs, that usually means shorter review cycles, stronger ownership metadata, and stronger linkage to Ultimate Guide to NHIs — Key Challenges and Risks, where excessive privilege and weak visibility are persistent drivers of exposure.
There is no universal standard for this yet, but the direction is clear: access reviews should confirm necessity, not just continuity. If the workflow cannot show why the access still exists, approval is usually masking governance debt rather than managing it. That is why review programs need joiner-mover-leaver discipline, secret rotation, and a defined offboarding path for every non-human identity.
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-03 | Review approvals often preserve overprivileged NHI credentials. |
| NIST CSF 2.0 | PR.AC-4 | Access reviews are identity governance controls for least privilege. |
| NIST AI RMF | Risk-based review decisions need context and accountability. |
Add context, ownership, and impact signals so access decisions are auditable and risk-aware.
Related resources from NHI Mgmt Group
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Reviewed and updated by the NHIMG editorial team on July 8, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
