Reviewers lose the evidence needed to tell whether access is still justified, exercised, or simply left in place. That weakens certification quality and lets stale entitlements persist. In PCI DSS 4.0 environments, access review without usage evidence becomes a paperwork exercise rather than a governance control.
Why This Matters for Security Teams
When access reviews are cut off from usage logs, certifiers are forced to approve or revoke access without evidence of how the entitlement is actually used. That creates blind spots in service accounts, API keys, and automation accounts where access can remain active long after the original business need has changed. The result is weaker certification quality and a larger attack surface, especially in environments already struggling with NHI visibility, as noted in the Ultimate Guide to NHIs.
This is not just an audit inconvenience. Access reviews are meant to validate necessity, scope, and ownership. Usage logs provide the evidence that turns a checkbox review into a defensible control. Without that linkage, reviewers may rely on stale owner attestations, incomplete inventories, or assumptions about job function. OWASP’s Non-Human Identity Top 10 treats visibility and lifecycle weaknesses as core risks for exactly this reason. In practice, many security teams discover excessive access only after a credential has already been reused, not through a clean certification cycle.
How It Works in Practice
A usable review process connects each entitlement to a concrete activity trail: authentication events, token use, API calls, job execution, and administrative actions. Reviewers then compare what was granted against what was actually exercised during the review window. That allows them to answer practical questions: is the account still in use, is it used for the intended workload, and does the observed scope match the approved scope?
In mature environments, the process usually looks like this:
- Inventory the identity, owner, purpose, and approved systems for each NHI.
- Collect usage telemetry from IAM, cloud logs, SaaS audit logs, and secrets managers.
- Correlate activity with the entitlement being reviewed, including last use and frequency.
- Flag dormant, overbroad, or anomalous access for recertification or removal.
- Record the reviewer decision together with the evidence used to make it.
This approach aligns with the lifecycle and offboarding emphasis in the NHI Lifecycle Management Guide and with the governance expectations in PCI DSS 4.0, where access reviews should reflect actual need rather than legacy assignment. NIST’s SP 800-53 Rev. 5 also reinforces the need for auditable access control and accountability evidence. The operational goal is simple: prove whether access is still justified by showing whether it is still exercised. These controls tend to break down when logs are fragmented across tools or retention windows are too short to cover the review period because reviewers cannot reconstruct actual usage.
Common Variations and Edge Cases
Tighter evidence requirements often increase review effort, so organisations must balance stronger certification with the overhead of collecting and normalising logs. That tradeoff becomes more visible in cloud-native and CI/CD-heavy environments, where a single workload may touch multiple systems and generate noisy activity that is hard to interpret without context.
Current guidance suggests treating not all usage as equal. A service account that runs on a fixed schedule may look dormant between jobs, while an API key embedded in an integration can be heavily used by automation that no human remembers to update. In those cases, reviewers need owner attestations plus telemetry, not telemetry alone. The Ultimate Guide to NHIs and Key Challenges and Risks is clear that visibility gaps are common, and that means disconnected review workflows often under-detect stale access rather than overcorrecting it. Best practice is evolving toward continuous entitlement validation, but there is no universal standard for that yet.
Edge cases also include third-party service accounts, emergency access, and break-glass credentials. Those may be intentionally unused for long periods, so absence of log activity does not automatically mean the access should be removed. In those environments, policy needs exception handling, owner revalidation, and shorter review cycles tied to risk. Without that, the review process either becomes perfunctory or starts revoking legitimate automation.
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 surface, NIST CSF 2.0 set the technical controls, and PCI DSS v4.0 define the regulatory obligations.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-01 | Disconnected reviews fail to validate NHI purpose and usage evidence. |
| NIST CSF 2.0 | PR.AA-03 | Access accountability depends on auditable evidence of entitlement use. |
| PCI DSS v4.0 | 7.2.5 | PCI review expectations are weakened when usage evidence is absent. |
Tie each NHI recertification to logs showing actual use before approving retention.
