Unused access becomes risk because standing permissions accumulate long before anyone notices they are no longer needed. That gap increases the chance of excess privilege, weakens review quality, and complicates investigations. When teams cannot show actual use, they also struggle to justify renewal decisions or prove that access remains appropriate.
Why unused access turns into identity risk
Unused access is rarely harmless inventory. In identity security programmes, standing permissions create a quiet drift between what a user, service, or application can do and what it actually needs to do. That drift expands blast radius, makes access reviews less reliable, and leaves organisations defending entitlements they can no longer explain with evidence.
There is also a lifecycle problem. Permissions that are left in place after project changes, role changes, or workload changes become easier to forget, harder to justify, and more attractive to abuse. The longer access persists without use, the more likely it is to become an exception that survives on process inertia rather than business need.
For broader context, NHIMG’s Ultimate Guide to NHIs, Key Challenges and Risks covers the same visibility and over-privilege pattern from a non-human identity perspective, and the broader guide explains how Non-Human Identities are represented across service accounts, API keys, tokens, and certificates.
One useful benchmark from NHIMG’s research is that only 5.7% of organisations have full visibility into their service accounts. That matters because unused access is much easier to retain than to remove when teams cannot reliably see where permissions exist or who still owns them.
How unused access weakens reviews and renewal decisions
Access reviews are only as good as the evidence behind them. If a reviewer cannot distinguish between active access and dormant access, the review becomes a formality instead of a control. That is where unused access causes practical harm: it raises the chance of over-approving permissions simply because they are familiar, inherited, or too difficult to investigate in time.
This also affects renewal logic. When teams lack usage evidence, they tend to fall back on role names, historical approvals, or assumed business continuity needs. That creates a gap between entitlement and justification, especially in environments with shared accounts, long-lived credentials, or multiple approvers across application and infrastructure teams.
For practitioners, the strongest control signal is not whether access exists, but whether there is a current, defensible reason for it to exist. If that reason cannot be produced quickly, the programme is already carrying risk in the review process itself.
Unused access is also easier to miss when it sits inside broad roles or inherited groups. Current guidance from ISO/IEC 27002:2022 Information Security Controls, CIS Controls v8, and the NIST SP 800-207 Zero Trust Architecture all supports reducing implicit trust and keeping access decisions tied to current need rather than historical assignment.
What identity teams should do with dormant permissions
Unused access should be treated as a signal for entitlement cleanup, not just a reporting metric. If an account, token, or role has no meaningful use over a defined period, the default response should be to validate ownership, check whether the access is still required for operations, and remove or reduce it if the business case is weak.
That decision is easier when teams separate three states: active use, justified standby, and unjustified surplus. Active use supports retention. Justified standby may be acceptable for resilience or break-glass purposes, but it should be explicitly controlled and time-bound. Unjustified surplus should be removed, even if no abuse has been observed.
For programmes that need a standards anchor, OWASP Non-Human Identity Top 10 is a strong companion reference for over-privilege and secret hygiene, and ISO/IEC 27001:2022 Information Security Management reinforces the need to keep access aligned to the information security management system rather than legacy convenience.
Risk and Threat Considerations
Unused access becomes risky because dormant permissions are still exploitable even when no one is actively using them. If a credential is stolen, a role is inherited incorrectly, or an account is forgotten after a team change, the unused permission can become the easiest path to excessive access, lateral movement, or unnoticed abuse.
Failure mechanism: Access remains valid after the original business need has ended, so privilege accumulates faster than review processes can remove it. That weakens least-privilege enforcement and leaves stale permissions available for takeover, misuse, or accidental overreach.
Impact: Organisations retain attack surface they cannot justify, investigators face harder scoping when an account is compromised, and reviewers may approve access renewals without evidence that the permission is still necessary.
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 CIS Controls v8, NIST CSF 2.0 and NIST Zero Trust (SP 800-207) set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| CIS Controls v8 | 6 — Access Control Management | Unused access is an access control hygiene problem that requires periodic review and revocation. |
| 5 — Account Management | Dormant accounts and stale entitlements are managed through account lifecycle discipline. | |
| Recommendation — Review access regularly and revoke permissions that no longer have a current business need. Disable or remove accounts and entitlements that are no longer actively required. | ||
| NIST CSF 2.0 | PR.AA-01 — Identity Management, Authentication and Access Control | Unused access is reduced by aligning access decisions to current identity and authorization state. |
| PR.DS-01 — Data-at-Rest Protection | Excess access increases exposure to protected data, making entitlement scope directly relevant. | |
| Recommendation — Enforce current access decisions and remove standing permissions that lack active justification. Limit data access to current need so stale permissions do not broaden data exposure. | ||
| NIST Zero Trust (SP 800-207) | 3 — Policy Engine and Access Decisions | Zero trust access decisions should be continuously evaluated rather than left standing. |
| Recommendation — Re-evaluate access continuously and remove permissions that no longer satisfy policy. | ||
| OWASP Non-Human Identity Top 10 | NHI-01 — Identity Discovery and Inventory | Unused access often persists because identities and entitlements are not fully visible or inventoried. |
| NHI-03 — Privileged Access and Least Privilege | Unused access increases excess privilege and expands the attack surface. | |
| NHI-05 — Lifecycle and Offboarding | Dormant access is a lifecycle failure when permissions remain after their business purpose ends. | |
| Recommendation — Inventory all identities and entitlements so dormant access can be found and removed. Reduce entitlements to least privilege and remove standing access that is no longer needed. Tie access removal to lifecycle events and offboarding rather than relying on later discovery. | ||
Practitioner Guidance
What to verify: Before renewing access, require current usage evidence, an identified owner, and a clear business justification. If any one of those is missing, treat the permission as a cleanup candidate rather than a routine renewal.
Common mistake: Teams often confuse “not recently challenged” with “still needed.” That shortcut is dangerous because dormant access tends to survive exactly where review discipline is weakest, such as inherited groups, service credentials, and exception-based approvals.
What good looks like: The programme can show which permissions are active, which are standby by design, and which are overdue for removal. Access that is never used should be rare, documented, and time-bound, not an invisible layer of standing privilege.
Practitioner takeaway: The real control objective is not to count permissions, but to keep every retained permission defensible in real time; if you cannot explain why it still exists, you should assume it is already risk.
