The governance principles are the same, but the lifecycle mechanics differ. Human accounts change with jobs and departures, while service and machine accounts need explicit ownership, narrower scope and secrets-specific review. A single control framework should cover both, but the operating model must reflect the identity type.
Why the governance model should be shared, but not the operating model
Human and non-human credentials are both access-bearing assets, so the governance questions are similar: who owns them, what they can reach, how they are reviewed, and when they are revoked. The difference is operational. Humans change through hiring, role moves and exits; service and machine credentials are better managed through explicit owners, tighter scope, and lifecycle rules that reflect automation.
That distinction matters because the same policy language can hide very different failure modes. A user account can usually be tied to a person and HR event, while a service credential may outlive the system, pipeline or workload that created it. In practice, the control model should be unified at the policy layer and differentiated at the enforcement layer.
For a shared governance model, the useful unit is not “human versus machine” alone, but “credential with an accountable owner and a defined purpose.” That lets organisations apply one standard for approval, review, rotation and revocation while still setting different defaults for session length, renewal, break-glass handling and secret storage depending on the credential type.
Where the lifecycle diverges in practice
Human credentials usually follow employment lifecycle signals: onboarding, transfers, leave and departure. Non-human credentials follow technical and operational lifecycle signals: workload creation, application release, environment changes, dependency retirement and secret expiry. If the organisation treats those as the same process, reviews drift toward either too much manual work or too little control.
Service and machine credentials also need narrower scope because they are often used programmatically and at scale. A credential that is acceptable for a person with interactive oversight is usually too broad for an unattended workload. That is why ownership, purpose limitation and periodic review matter more than just the account label.
Rotation and offboarding are also different. Human offboarding is anchored in people processes, but non-human offboarding must be explicit because systems can keep using stale secrets long after the business owner thinks the asset is gone. Guidance on NHI rotation challenges and NHI ownership and accountability shows why dependency mapping and named accountability are central for these lifecycles.
How to design one control framework without forcing one workflow
The best pattern is a single governance policy with multiple operating procedures. That means one set of decision rights for approval, exceptions, recertification and audit evidence, but separate runbooks for people accounts, service principals, API keys, workload identities and shared automation credentials. A useful common control is to require an owner, a business purpose, a scope statement and a review cadence for every credential.
For the non-human side, the operating model should treat secrets as credentials that need their own controls, not as miscellaneous configuration. Practical secret management depends on lifecycle discipline, which is why a secrets management guide and a focused API key management guide are useful complements to a general identity policy. Where people and machines meet, the human versus non-human identity distinction is the one that keeps governance aligned with actual usage rather than job titles.
External guidance supports the same split. OWASP’s Non-Human Identity Top 10 is helpful for the machine side because it frames overprivilege, rotation and secret exposure as first-class governance problems. For the general control plane, the NIST SP 800-53 Rev. 5 Security and Privacy Controls catalog remains a sensible common language for access control, authentication and auditability.
Risk and Threat Considerations
When organisations apply a human-centric process to machine credentials, the result is usually silent overexposure: stale secrets, orphaned accounts, excessive privilege and missed revocation. The threat is not only theft, but also persistence, because unattended credentials can keep working long after the original owner or system boundary has changed.
Failure mechanism: The control breaks when ownership is implicit, review is calendar-based rather than lifecycle-based, or rotation depends on manual intervention that never keeps pace with automation.
Impact: Attackers or insiders can reuse long-lived credentials to move laterally, access production systems, or consume services without obvious user-facing symptoms, while the organisation loses confidence that revocation actually means revocation.
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 API Security Top 10 address the attack and risk surface, while NIST SP 800-53 Rev 5 and CIS Controls v8 set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-01 — Improper Offboarding | Human and non-human credentials both need revocation paths when their owners or systems change. |
| NHI-05 — Overprivileged NHI | Non-human credentials need narrower scope because unattended access magnifies blast radius. | |
| NHI-07 — Long-Lived Secrets | The question hinges on different lifecycle mechanics for credentials that can persist beyond people or systems. | |
| Recommendation — Define explicit offboarding triggers and revoke non-human credentials when the owning system or team changes. Restrict machine and service credentials to the minimum permissions needed for each workload. Set short expiry and rotation requirements for secrets that authenticate non-human access. | ||
| NIST SP 800-53 Rev 5 | IA-5 — Authenticator Management | Both human and non-human credentials require lifecycle control, rotation and revocation. |
| AC-6 — Least Privilege | Shared governance still requires tighter scope for service and machine credentials. | |
| AU-6 — Audit Record Review, Analysis, and Reporting | Unified governance needs review evidence for both human and non-human access decisions. | |
| Recommendation — Manage issuance, rotation and revocation of all authenticators through a formal lifecycle process. Limit each credential to the minimum access required for its defined purpose. Review credential activity and exceptions regularly to detect stale or excessive access. | ||
| OWASP API Security Top 10 | API5 — Broken Function Level Authorization | Programmatic credentials must not inherit broad permissions simply because they are non-interactive. |
| Recommendation — Enforce function-level authorization so machine credentials can only call approved actions. | ||
| CIS Controls v8 | CIS-5 — Account Management | The topic is fundamentally about governing different credential populations across their lifecycle. |
| Recommendation — Inventory, approve, review and remove both human and non-human accounts on a defined schedule. | ||
Practitioner Guidance
What to prioritise: Put every credential into one governance register, then classify it by actor type, business purpose and lifecycle trigger. The key decision is whether the credential’s review and revocation path can be automated or must remain exception-managed.
What to verify: Confirm that each non-human credential has a named owner, a defined scope, a rotation rule and a retirement condition. If you cannot tie a credential to an accountable team and a concrete technical dependency, treat it as an unmanaged exposure.
Common mistake: Using the same approval form for humans and machines, but leaving machine credentials to age indefinitely because “no one owns the workload.” The governance model can be shared, but the operating discipline cannot be generic.
Practitioner takeaway: Standardise the policy, diversify the mechanics, and make lifecycle ownership explicit wherever a credential can still act after the person or system that created it has changed.
Related resources from NHI Mgmt Group
- Should organisations use the same policy model for humans and non-human identities?
- Should organisations treat NHI secrets and human credentials under the same governance model?
- Should organisations include contractors, bots, and non-human identities in the same governance model?
- What breaks when organisations use one IAM model for humans and non-human identities?