TL;DR: Zero trust reduces implicit trust by requiring verification, device checks, encryption, least privilege, monitoring, and periodic access review, according to Axiad. The governance problem remains the same: programmes that ignore permission creep and access sprawl still leave identity attack surface open.
At a glance
What this is: Axiad explains that zero trust implementation breaks down when permission creep and access sprawl are not controlled, allowing users to accumulate more access than their roles justify.
Why it matters: IAM, IGA, and PAM teams need to treat entitlement growth as an active zero trust failure mode, because excessive access undermines verification, least privilege, and ongoing trust decisions.
Context
Zero trust is a security model built on explicit verification rather than assumed trust. In practice, that means users, devices, and access paths must be checked continuously, but the model weakens if permissions keep expanding after initial approval.
Axiad’s article argues that the most common implementation gap is not the absence of policy language but the gradual buildup of unnecessary access. Permission creep turns least privilege into a moving target, which is why identity governance has to be part of zero trust from the start.
Key questions
Q: What breaks when permission creep is not controlled in a zero-trust programme?
A: The model stops being dynamic and becomes a new wrapper for old standing access. Privileges accumulate, access reviews turn into paperwork, and teams lose the ability to prove that the current entitlement set matches current need.
Q: Why do MFA and device checks not solve permission creep risk?
A: MFA and device posture checks verify who or what is asking for access, but they do not reduce excessive permissions already granted. If roles, groups, and exceptions are not trimmed, a verified user can still reach far more data and systems than the current task justifies.
Q: How should security teams modernize access reviews in zero trust programmes?
A: They should move from broad, calendar-based approvals to evidence-based reviews that focus on actual usage, role fit, and exception handling. Access reviews work best when they are tied to lifecycle events such as role changes and offboarding, and when reviewers see context that explains why an entitlement exists. The goal is fewer rubber-stamp approvals and faster removal of stale access.
Q: What is the difference between zero trust authentication and entitlement governance?
A: Authentication verifies the identity and the device at the point of access. Entitlement governance controls what that identity can do after access is granted, which is where permission creep appears. Zero trust needs both, but they solve different parts of the trust problem.
Technical breakdown
Why permission creep breaks least privilege
Permission creep is the slow accumulation of access rights that were once justified but no longer match the user’s role or task set. In zero trust, least privilege depends on the ability to bound access tightly and re-evaluate it over time. If entitlements are never reduced, the identity becomes more powerful than its current business need, and the access model stops reflecting actual trust conditions. That creates an identity attack surface that grows silently even when authentication controls remain strong.
Practical implication: review entitlement growth as a zero trust control failure, not just an access hygiene issue.
How MFA and device verification still leave entitlement risk behind
MFA and device checks verify the actor and the endpoint, but they do not fix stale or excessive permissions once access is granted. A zero trust programme can authenticate well and still fail governance if users retain broad roles, nested group membership, or accumulated exceptions. The issue is not identity proof alone but authorization drift after proof. That is why access decisions and access maintenance need to be governed as separate layers, even when the front door is strong.
Practical implication: pair strong authentication with entitlement governance, or access sprawl will continue underneath it.
Why periodic access review is only effective when roles stay current
Periodic access review is meant to catch access that no longer matches business need, but its value depends on timely role cleanup and accurate ownership. When roles are broad, inherited, or rarely revalidated, reviews become paperwork rather than control. Zero trust assumes trust is revisited as conditions change. Without regular pruning of entitlements, review cycles simply confirm a broken baseline instead of correcting it.
Practical implication: align recertification with role design and entitlement cleanup, not just with audit dates.
Breaches seen in the wild
- Co-op cyber attack 2025: Attackers linked to Scattered Spider tricked their way into a Co-op employee account and stole personal data of all 6.5 million members.
Read and download The State of NHI & AI Agent Breach Report 2026, covering 150+ breaches impacting Non-Human Identities including AI Agents.
NHI Mgmt Group analysis
Permission creep is a zero trust failure mode, not a side effect. A zero trust programme can be architecturally sound at the point of authentication and still collapse in practice if users accumulate access over time. That accumulated privilege creates an identity attack surface that the initial trust decision never intended. Practitioners should treat entitlement growth as a governance defect with security impact, not as a routine admin issue.
Least privilege only works when it is continuously re-bounded. Zero trust is often described as a set of controls, but its real discipline is ongoing constraint. If access rights are allowed to drift upward, the model quietly reverts to implicit trust inside the enterprise. The practical conclusion is that access scope must be managed as a living control plane, not a one-time provisioning outcome.
Identity attack surface expansion is the right name for permission creep. That phrase captures the fact that every unnecessary role, inherited privilege, and exception widens the set of things an attacker can abuse after compromise. A zero trust programme that ignores this expansion is measuring authentication strength while leaving authorization decay untouched. Identity teams should use that term to connect IAM, IGA, and PAM work to zero trust outcomes.
Zero trust governance must include entitlement lifecycle management. The article’s core message is that verification alone does not preserve security posture if access is allowed to compound. That puts lifecycle ownership, recertification discipline, and privilege cleanup in the centre of the zero trust programme. The practitioner conclusion is simple: if access can grow without friction, zero trust is already being undermined.
Permission creep is where zero trust meets operational reality. The model’s promise depends on disciplined administration across roles, exceptions, and changing user needs. As organisations scale, those controls fail first in the places that are least visible: inherited group memberships, dormant entitlements, and exceptions that never expire. Identity leaders should expect the weak point to be governance, not authentication.
From our research library:
- 90% of IT leaders say properly managing NHIs is essential for a successful zero-trust implementation, according to the Ultimate Guide to NHIs.
- By 2029, 40% of enterprises that successfully implement zero trust within cloud service provider environments will rely on the advanced visibility and control capabilities offered by CNAPP solutions.
- Read next: NHI Lifecycle Management Guide
What this signals
Identity attack surface expansion: zero trust programmes that focus only on login strength miss the governance problem that grows underneath them. When roles, exceptions, and inherited permissions are left to compound, the control plane starts to reward historical access rather than current need, and that is where least privilege fails in practice.
A useful way to frame the issue is that authentication proves a session, while entitlement management governs the session’s blast radius. If access review and role cleanup do not keep pace with organisational change, the zero trust model becomes a perimeter replacement without a true authorization discipline.
For practitioners
- Audit entitlement growth patterns Identify where roles, group memberships, and exceptions have expanded beyond current job requirements, then flag those paths as zero trust exceptions requiring cleanup.
- Separate authentication from authorization governance Keep MFA and device verification in place, but add a distinct entitlement review process so excessive access is not mistaken for trusted access.
- Tighten role definitions before recertification Reduce broad or inherited roles before access review cycles so recertification validates current business need instead of preserving historical sprawl.
- Track permission creep as a zero trust metric Measure how many users carry unused or expanded permissions over time, and use that signal to prioritise remediation in IAM and IGA.
Key takeaways
- Permission creep is the practical reason many zero trust programmes underperform, because access expands faster than governance catches it.
- The core evidence in the article is that strong authentication, device checks, encryption, and monitoring still leave excessive access untouched if entitlement drift is unmanaged.
- The control that changes the outcome is disciplined entitlement cleanup, supported by recurring review of roles, exceptions, and accumulated permissions.
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 and MITRE ATT&CK address the attack and risk surface, while NIST CSF 2.0 and NIST SP 800-53 Rev 5 set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-05 — Overprivileged NHI | Permission creep is an over-authorization problem that mirrors NHI privilege growth. |
| Recommendation — Map access growth to NHI-05 and remove standing permissions that exceed current task need. | ||
| NIST CSF 2.0 | PR.AA-05 — Access Permissions, Entitlements and Authorizations | The article is about keeping authorizations aligned with zero trust assumptions. |
| Recommendation — Apply PR.AA-05 to recertify entitlements and remove permissions that no longer match role need. | ||
| NIST SP 800-53 Rev 5 | AC-6 — Least Privilege | Least privilege is the core control undermined by permission creep in zero trust. |
| Recommendation — Use AC-6 to narrow access rights and prevent privilege accumulation over time. | ||
| MITRE ATT&CK | TA0004;TA0006 — Privilege Escalation; Credential Access | Excessive permissions increase the impact of stolen credentials and escalation opportunities. |
| Recommendation — Map excess entitlements to TA0004 and TA0006 when prioritising identity attack-surface reduction. | ||
Key terms
- Permission Creep: The gradual accumulation of access beyond what a user or workload currently needs. It usually happens because initial approvals are never fully removed or recertified. In practice, permission creep is a lifecycle failure that turns temporary exception access into de facto standing privilege.
- Least Privilege: A security principle requiring that every identity, human or non-human, is granted only the minimum permissions necessary to perform its function. Least privilege is the single most effective control for reducing NHI blast radius.
- Entitlement Governance: Entitlement governance is the discipline of deciding who or what should have access, for how long, and under what business justification. It spans human users, non-human identities, and automated workflows, making it a core control layer for SaaS, cloud infrastructure, and lifecycle management.
- Identity Attack Surface: Identity attack surface is the total set of accounts, tokens, login endpoints, trust paths, and supporting systems that can be probed for access. For password spraying, the risk grows with every externally reachable authentication path and every dormant or weakly protected identity.
Deepen your knowledge
NHI governance, agentic AI identity, and machine identity lifecycle are core topics in our NHI Foundation Level course, the industry's only accredited NHI security programme. If you are responsible for identity security strategy or NHI governance in your organisation, it is worth exploring.
Published by the NHIMG editorial team on June 12, 2026.
Updated on October 8, 2026.
NHI Mgmt Group, the independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org