They were designed to certify roles and approvals for human users, not to interpret continuous machine activity, ownership or downstream business transactions. That leaves a gap between access being granted and access being understood in operational context.
Why Legacy IGA Models Miss Non-Human Identities
Legacy IGA tools were built around people: joiner-mover-leaver events, role mining, manager approvals, and periodic certification of human entitlements. Non-human identities behave differently. Service accounts, API keys, workload identities, and automation bots can act continuously, change context without a staffing event, and trigger downstream business transactions that a role review never sees. That is why the old model often records access but not operational meaning.
In practice, the gap becomes visible only when an automation path fails, a credential is overused, or an ownership question blocks response. NHIMG research shows that 97% of NHIs carry excessive privileges, which is a strong indicator that broad entitlement assignment, not just missing review, is the real problem.
Many teams discover this only after the machine identity has already moved data, changed state, or exposed a system in ways the IGA workflow was never designed to interpret.
How Machine Activity Breaks Traditional Certification Workflows
Human-centric IGA assumes an identity can be reviewed by a manager who understands its business purpose, inactivity can be detected from login patterns, and access can be recertified on a calendar. Those assumptions collapse for NHI estates. An API key may never “log in” like a person, yet it may authenticate thousands of times a day. A service account may have no obvious owner in HR, but still control production data. A CI/CD robot may be technically valid while being operationally obsolete.
That creates three practical failures. First, ownership is often ambiguous, so approvals are routed to the wrong team or avoided altogether. Second, entitlement review is detached from runtime context, so a permission that is harmless in one pipeline can become high-risk in another. Third, revocation and rotation are treated as exceptional clean-up tasks rather than normal identity hygiene.
- Static role models cannot express ephemeral workload access well.
- Certification campaigns do not reveal whether a credential is still actively used by automation.
- Business approvers usually cannot validate machine-to-machine necessity from an entitlement list alone.
For that reason, modern NHI governance usually needs lifecycle controls, ownership metadata, and usage signals alongside access approvals. The goal is to know not only that access exists, but whether it still serves a current workload, who can revoke it, and what downstream systems it can reach. Current guidance suggests that identity review without operational telemetry leaves a blind spot, and the NHI Mgmt Group guide on non-human identity governance is a useful reference point for that shift. Traditional IGA breaks down most sharply when machine credentials are embedded in code or CI/CD because the tool sees a principal, but not the automation path that actually consumes it.
Where the Gaps Become Operational and Governance Risks
Tighter governance around NHIs increases overhead, because every machine credential needs ownership, scope, rotation, and revocation logic that is more granular than a human joiner-mover-leaver process. That tradeoff is unavoidable, because the failure mode is not just missed certification; it is silent persistence of access.
Legacy IGA also struggles when downstream transactions matter more than raw entitlement status. A service account may be formally approved, yet still create excess exposure if it can write to production, invoke privileged APIs, or act across environments. That is why some teams treat NHI review as a secrets problem, while others treat it as a workload-authorization problem. Best practice is evolving, and there is no universal standard for this yet, but both views are incomplete if they do not connect identity to actual machine behaviour.
One useful external reference for the control side is NIST SP 800-53 Rev 5 Security and Privacy Controls, especially where organisations need to align identity governance with access enforcement and account management outcomes rather than annual review alone. In practice, teams that keep treating NHIs as if they were dormant human accounts tend to miss exposure until rotation, outage recovery, or incident response forces the question of who actually owns the access.
Risk and Threat Considerations
The main risk is governance failure that turns into security exposure. When legacy IGA cannot interpret continuous machine activity, organisations can leave high-impact credentials active long after the business need has changed. That creates standing access, weak accountability, and poor visibility into what systems a machine identity can still reach.
Failure mechanism: Human-centric certification and approval workflows do not model non-interactive authentication, so overprivileged service accounts, API keys, and workload identities remain valid, reusable, and poorly owned. Attackers and abuse cases benefit from that gap because a compromised NHI can persist without triggering the human lifecycle checks the IGA tool was designed to enforce.
Impact: The result is broader blast radius, slower revocation, and delayed detection of unauthorized transactions or lateral movement through machine-to-machine trust paths. It also weakens auditability because the organisation can prove that access was approved, but not that it was still justified or safely bounded when used.
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 OWASP Agentic AI 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 |
|---|---|---|
| OWASP Non-Human Identity Top 10 | Lifecycle Governance — Lifecycle Governance | NHI lifecycle and ownership gaps are the core reason legacy IGA struggles here. |
| Recommendation — Inventory, assign owners, and revoke machine identities on lifecycle events rather than human review cycles. | ||
| CIS Controls v8 | 5 — Account Management | The issue centers on unmanaged accounts, keys, and stale access paths. |
| Recommendation — Track every non-human account and remove or disable it when its business purpose ends. | ||
| NIST CSF 2.0 | PR.AA — Identity Management, Authentication, and Access Control | The question concerns identity governance failing to reflect actual access use and scope. |
| GV.RM — Risk Management Strategy | NHI blind spots create governance and exposure risk that needs explicit treatment. | |
| Recommendation — Link identity governance to actual authentication scope and continuously validate access necessity. Classify NHI governance gaps as material risk and track them in the organisation's risk register. | ||
| NIST Zero Trust (SP 800-207) | PL-3 — Policy and Enforcement | Machine access must be enforced dynamically instead of assumed safe after approval. |
| Recommendation — Enforce policy decisions at runtime for machine identities instead of relying on static approvals. | ||
| OWASP Agentic AI Top 10 | A1 — Agentic Access Control | Autonomous or automated identities need context-aware authorization beyond human IAM patterns. |
| Recommendation — Apply context-aware access controls to autonomous agents and bound their permissions to task scope. | ||
Practitioner Guidance
What to prioritise: Treat ownership, usage, and revocation as the core NHI controls, not as metadata. If an identity cannot be tied to a system owner, a workload, and a revocation path, it is not ready for ordinary IGA treatment.
What to verify: Confirm that the review process checks live machine activity, credential age, and environment scope, not just entitlement presence. A valid approval is not enough if the credential is still reusable in production, cross-environment, or after workload decommissioning.
Practitioner takeaway: The practical test is whether the governance process can explain machine access in operational terms, not merely certify that it was once approved.
Related resources from NHI Mgmt Group
- Why do legacy identity tools struggle as organisations add more non-human identities and AI-driven access?
- How should security teams govern non-human identities at scale?
- How should security teams govern non-human identities for compliance?
- Why do non-human identities create more audit risk than human accounts?
Deepen Your Knowledge
Reviewed and updated by the NHIMG editorial team on September 6, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
