They often treat access reviews as a documentation task instead of a control that must prove scope, ownership, and remediation. Under NIS2, a review that cannot show who approved access, what changed, and when privileges were removed is weak evidence. The review must be tied to real access reduction, not just completed on schedule.
Why This Matters for Security Teams
NIS2 turns access reviews into evidence of operational control, not a paperwork exercise. Teams that only confirm a review was “completed” miss the point: auditors and regulators care about whether access was scoped correctly, whether owners were accountable, and whether unnecessary privilege was actually removed. That distinction becomes sharper when non-human identities and service accounts are included, because these entitlements often outlive the human approver and drift far beyond the original need.
The practical risk is that review programs become predictable, calendar-driven checklists while real privilege accumulation continues in the background. NHI Mgmt Group’s Ultimate Guide to NHIs notes that only 5.7% of organisations have full visibility into their service accounts, which explains why review evidence often fails when asked to prove actual removal. The regulatory expectation is better reflected in the NIS2 Directive, where governance and risk treatment must be demonstrable, not implied. In practice, many security teams discover weak access review evidence only after an audit request or incident has already exposed the gap.
How It Works in Practice
Effective NIS2 access reviews start with a complete entitlement inventory, then move into ownership, business justification, and remediation tracking. The review is not just “who has access,” but “why does this access still exist, who can approve it, and what happened after the review?” That is where many programmes fail: they can show a signed spreadsheet, but not the downstream reduction in permissions. Current guidance suggests evidence should connect review outcome to actual entitlement changes, especially where privileged or shared accounts are involved.
A usable process usually includes:
- scoping all identities, including service accounts, API keys, and administrative roles;
- requiring a named owner for each access decision, not a generic team mailbox;
- capturing the rationale for retention, reduction, or removal;
- tracking remediation to closure with timestamps and approval history;
- revalidating exceptions on a shorter cycle than standard user access.
This is consistent with the NHI lifecycle and audit perspective discussed in NHI Lifecycle Management Guide and Ultimate Guide to NHIs — Regulatory and Audit Perspectives. For execution, many teams map review evidence to control objectives in the OWASP Non-Human Identity Top 10 so the review includes rotation, offboarding, and privilege reduction rather than access attestation alone. These controls tend to break down when entitlement data is fragmented across SaaS, cloud IAM, and code repositories because no single owner can prove the full before-and-after change.
Common Variations and Edge Cases
Tighter access reviews often increase operational overhead, so organisations have to balance auditability against review fatigue and business disruption. That tradeoff matters most where access is highly dynamic, such as DevOps pipelines, break-glass accounts, and third-party integrations. Best practice is evolving here: there is no universal standard for how often every non-human entitlement must be revalidated, but the review frequency should reflect risk, blast radius, and credential lifespan.
One common mistake is treating long-lived access as acceptable if it is “well documented.” For NIS2, documentation without remediation is weak evidence. Another is excluding machine identities because the review workflow was designed for employees. That leaves the highest-risk access paths outside the control. NHI Mgmt Group’s research shows that 97% of NHIs carry excessive privileges, which is exactly why reviews must be used to drive reduction, not just record approval. The 52 NHI Breaches Analysis is useful for understanding how these gaps become incident paths rather than administrative issues. In practice, review programmes fail fastest in environments with delegated admin, shared service accounts, or outsourced operations because ownership is unclear and revocation steps are not owned end to end.
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 NIS2 define the regulatory obligations.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIS2 | NIS2 requires demonstrable governance, not just scheduled review completion. | |
| OWASP Non-Human Identity Top 10 | NHI-03 | Access reviews must reveal stale NHI privileges and enforce removal. |
| NIST CSF 2.0 | PR.AC-4 | Least-privilege access review discipline aligns with access governance. |
Tie access reviews to actual remediation evidence, ownership, and privilege reduction.
