Why do manual user access reviews create compliance risk?

Why This Matters for Security Teams

Manual access reviews are risky because they try to prove a control through human effort rather than through durable system evidence. Spreadsheets, exports, and email follow-up can show intent, but they do not reliably prove that access was evaluated, approved, revoked, and retained in a way an auditor can trust. That gap matters most in regulated environments where review completion, timeliness, and traceability are part of the control itself.

The problem is larger when non-human identities are in scope. NHIs outnumber human identities by 25x to 50x in modern enterprises, and the Ultimate Guide to NHIs notes that only 5.7% of organisations have full visibility into their service accounts. In that environment, manual review files often lag reality. Current guidance from the NIST Cybersecurity Framework 2.0 and the OWASP Non-Human Identity Top 10 both point toward stronger identity governance, but the control objective is easy to miss when the evidence trail is assembled by hand. In practice, many security teams discover access-review failures only after a sampling exception, stale entitlement, or missed revocation has already created an audit finding.

How It Works in Practice

Manual reviews usually start with an export from an IAM or SaaS platform, then move into spreadsheet-driven attestations, manager sign-off, and ticket-based follow-up. The operational challenge is that each step introduces drift. Access can change after the export, reviewers may not understand the privilege context, and remediation tickets can close before the underlying entitlement is actually removed. For NHIs, this is worse because service accounts, API keys, and tokens often have no obvious owner and may be embedded in pipelines or application configs. The Ultimate Guide to NHIs — Regulatory and Audit Perspectives is useful here because it frames auditability as a lifecycle problem, not a one-time review task.

A stronger approach is to move from manual attestation to continuously governed evidence. That typically includes:

• system-generated access snapshots with immutable timestamps and approver identity
• automated revocation workflows tied to role changes, inactivity, or termination events
• documented exceptions with expiry dates and compensating controls
• segregation of human and NHI reviews so service-account access is not buried in user spreadsheets

Where possible, organisations should align review evidence with control mappings from OWASP Non-Human Identity Top 10 and identity governance practices described in Top 10 NHI Issues. That reduces the chance that a reviewer signs off on an entitlement they cannot actually validate. These controls tend to break down when access is scattered across shadow IT, shared admin accounts, and embedded secrets because the review source data is incomplete before the review even begins.

Common Variations and Edge Cases

Tighter review controls often increase operational overhead, requiring organisations to balance audit defensibility against the cost of automation and exception handling. That tradeoff is real in fast-moving environments where application owners, platform teams, and compliance staff each own part of the access picture.

Best practice is evolving for NHIs because there is no universal standard for how often every service account, token, or API key must be revalidated. In some environments, quarterly certification may be acceptable for low-risk entitlements, while privileged or externally exposed access needs shorter cycles and stronger evidence. The main exception is emergency access, where a human review may be necessary, but the review should still be backed by machine-enforced expiry and logging rather than a retrospective spreadsheet note.

Manual reviews also become weaker when teams conflate ownership with approval. A line manager may be able to attest to a person’s role, but not to the necessity of a CI/CD token, a database credential, or a third-party integration key. The most defensible approach is to combine human attestation with system controls, then use NHI lifecycle guidance to ensure access is reviewed, rotated, and revoked on a predictable schedule. When entitlement data comes from multiple IAM, SaaS, and pipeline tools, manual certification tends to fail because no single reviewer can reliably validate the full access chain.

Related resources from NHI Mgmt Group

• Why does break-glass access create so much audit and compliance risk?
• Why do shared devices create more access risk than single-user devices?
• Why do non-human identities create compliance risk even when policies exist?
• When do NHI access reviews create more value than a one-time cleanup?