The identity governance function should own the policy, but system owners must validate business need and asset owners must confirm risk tolerance. Human accounts, service accounts, and tokens all need the same lifecycle discipline, because overprivilege in any one of them can expand the same blast radius.
Why This Matters for Security Teams
least privilege becomes a governance problem the moment human users and machine identities share sensitive access paths. The policy may look uniform on paper, but the risk is not uniform in practice. A human admin, a service account, and an API token fail differently, expire differently, and create different blast radii when overused. That is why identity governance should own the policy baseline, while system owners validate need and asset owners confirm acceptable risk.
NHIMG research shows the gap is already visible in production environments: in the 2026 Infrastructure Identity Survey, 70% of organisations grant AI systems more access than they would give a human employee doing the same job. That pattern reflects a broader control failure, not a narrow AI issue. The same discipline discussed in the Ultimate Guide to NHIs applies across both identity types: ownership, review, rotation, and revocation cannot stop at the human side of the house. Current guidance also aligns with the OWASP Non-Human Identity Top 10 and NIST SP 800-207 Zero Trust Architecture, both of which treat identity context and continuous verification as core controls, not exceptions. In practice, many security teams encounter privilege creep only after a machine identity has already widened access beyond what any human reviewer approved.
How It Works in Practice
Ownership should be split by control function, not by identity type. Identity governance defines the policy, review cadence, and evidence requirements. System owners attest that the access is needed for a specific workload or business process. Asset owners decide whether the resulting risk is tolerable for the system under their control. That division keeps least privilege from becoming either a purely technical setting or an abstract policy statement.
For human identities, this usually means role review, access certification, and time-bounded elevation through PAM or JIT workflows. For machine identities, the same outcome is reached differently: short-lived credentials, scoped tokens, workload identity, and explicit task boundaries. The critical idea is that a token or service account should prove what it is allowed to do right now, not what it has historically been allowed to do. That is why many practitioners now pair least privilege with runtime controls, policy-as-code, and strong workload identity rather than relying on static group membership alone.
- Use a single least-privilege policy standard for humans and machines, but adapt the enforcement mechanism to the identity class.
- Require system owners to justify every sensitive entitlement with a business process or workload description.
- Require asset owners to approve the risk impact of elevated access on the protected system.
- Prefer ephemeral credentials and scoped tokens over long-lived secrets stored in code or config.
- Revoke on task completion, not on a calendar cycle alone.
The operational model is supported by NHI governance guidance in the Ultimate Guide to NHIs — Key Challenges and Risks, which highlights how excessive privilege and poor visibility compound each other. In many environments, the same policy exception that seems harmless for a service account becomes dangerous when copied to an AI agent that can chain tools or act without human pacing. These controls tend to break down when access is granted through ad hoc cloud roles and unmanaged tokens because no owner can prove who approved the privilege, for what workload, or how quickly it will be removed.
Common Variations and Edge Cases
Tighter least-privilege governance often increases administrative overhead, so organisations have to balance speed against auditability. That tradeoff is especially sharp when engineering teams want reusable machine access for automation, but security teams need per-task scoping and frequent revocation. Current guidance suggests the answer is not to relax the control, but to automate the review and issuance path so ownership stays clear even when the entitlement is temporary.
There is no universal standard for this yet in agentic or hybrid-human environments. Some organisations assign a single business owner to the full identity chain, while others split approval between the platform team and the application owner. The more sensitive the access, the less defensible it is to leave ownership ambiguous. If an identity can change configuration, move laterally, or touch production data, then least privilege must be reviewed as a living control, not a one-time ticket closure.
That distinction matters most for shared service identities, break-glass access, and AI-driven automation that can issue follow-on commands. Human accounts tend to be visible but slow to exploit; machine identities are often less visible and much faster to abuse. Security leaders should treat both as first-class identities, but they should never assume the same approval path fits both. Best practice is evolving toward context-aware review backed by the operational principles in The 2026 Infrastructure Identity Survey and the access discipline described in Ultimate Guide to NHIs.
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 | Least privilege depends on controlling NHI access scope and credential lifecycle. |
| NIST CSF 2.0 | PR.AC-4 | Access permissions must be managed and reviewed across human and machine identities. |
| NIST AI RMF | AI RMF requires governance for autonomous access decisions and accountability. |
Review every NHI entitlement against NHI-03 and remove standing access that is not tied to a current workload.
