Start by reducing manual review dependency on the highest-risk applications and entitlements first. Use authoritative lifecycle events for provisioning and deprovisioning, then certify access only where ownership and business purpose are visible. Manual review should become exception handling, not the primary operating model.
Why This Matters for Security Teams
Manual access reviews are still common, but they do not scale well when entitlements change faster than reviewers can validate business need. The real risk is not just review backlog, it is the accumulation of stale access, over-privileged accounts, and unowned exceptions that never get resolved. That problem is amplified for non-human identities, where lifecycle events, OAuth grants, and service account use often move outside the visibility of traditional IGA.
NHI Management Group’s Ultimate Guide to NHIs notes that only 5.7% of organisations have full visibility into service accounts, while 97% of NHIs carry excessive privileges. That gap is why a review-centric model can look healthy on paper and still leave significant exposure in production. Current guidance from the OWASP Non-Human Identity Top 10 is to treat entitlement sprawl and weak lifecycle control as first-order risks, not audit housekeeping.
In practice, many security teams discover that access reviews failed only after a dormant account, stale token, or inherited entitlement was already used to reach sensitive systems.
How It Works in Practice
The most effective way to modernise IGA is to reduce the number of decisions that depend on humans remembering why access exists. Start with the highest-risk applications, privileged roles, and non-human identities, then shift provisioning and deprovisioning to authoritative lifecycle events such as joiner-mover-leaver updates, contract termination, application decommissioning, and workflow completion. Reviews then become a validation step for unusual cases, not the primary control.
For non-human identities, this means connecting IGA to sources of truth for workload ownership, system purpose, and secret issuance. The NHI Lifecycle Management Guide is useful here because lifecycle is the control plane: if ownership, rotation, and offboarding are unclear, certification will be slow and unreliable. Teams should also separate human entitlements from machine access, because service accounts, API keys, and OAuth grants need different review criteria than employee roles.
- Use authoritative events to create, change, suspend, and revoke access automatically.
- Require business purpose, owner, and system context before an entitlement can enter review.
- Prioritise high-risk access by privilege, data sensitivity, and external exposure.
- Route only exceptions, conflicts, and unresolved ownership gaps to manual certification.
- Track review outcomes so revocations, not just approvals, are measurable.
Frameworks like CISA Zero Trust Maturity Model and the OWASP Non-Human Identity Top 10 both reinforce the same operational point: review should confirm least privilege, not compensate for missing lifecycle automation. These controls tend to break down in decentralised SaaS environments where app owners can grant access outside central provisioning workflows because ownership and revocation are fragmented across teams.
Common Variations and Edge Cases
Tighter review automation often increases governance overhead at first, because organisations must normalise identity data, map owners, and define which systems are authoritative. That tradeoff is worth making, but the rollout should be phased so reviewers are not overwhelmed by low-value attestations. Best practice is evolving, and there is no universal standard for how much automation is enough before manual certification can safely shrink.
Some environments still need manual review for regulated entitlements, emergency access, third-party integrations, and legacy systems that cannot emit dependable lifecycle events. In those cases, a risk-based model works better than a blanket annual attestation. The question is not whether access is reviewed manually, but whether manual review is reserved for the few cases where policy cannot yet be enforced automatically. The Ultimate Guide to NHIs shows why this matters: 92% of organisations expose NHIs to third parties, so ownership and offboarding gaps often surface in supplier-connected access first, not in core employee IAM.
Teams that keep manual review as the centre of gravity usually end up certifying noise instead of reducing exposure.
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 NIST CSF 2.0 and NIST AI RMF set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-03 | Covers lifecycle and rotation weaknesses that manual reviews often miss. |
| NIST CSF 2.0 | PR.AC-4 | Maps to access governance and least-privilege enforcement across identities. |
| NIST AI RMF | Supports governance, mapping, and monitoring of AI-driven access decisions. |
Use AI RMF governance to define ownership, review scope, and accountability for automated access actions.
