Should organisations treat service accounts like human users in access reviews?

Why This Matters for Security Teams

Service accounts should not be treated as human users in a one-to-one sense, but they absolutely belong in the same review process because they are still identities with access, ownership, and lifecycle risk. The difference is that human reviews focus on job function and user intent, while service account reviews must focus on workload purpose, dependency, and whether standing access is still justified. NHI Mgmt Group notes that NHIs outnumber human identities by 25x to 50x in modern enterprises, which makes them easy to overlook until an outage, audit finding, or incident exposes the gap. The OWASP Non-Human Identity Top 10 also highlights how overprivileged and unmanaged machine identities become repeatable attack paths.

That scale changes the review question from "Does this account belong to someone?" to "Is this credential still needed, by this workload, for this scope, under this ownership model?" In practice, many security teams encounter excessive privilege and stale service account access only after a breach review or access recertification failure, rather than through intentional governance.

How It Works in Practice

The practical approach is to include service accounts in the same enterprise access review cycle as humans, but to assess them with different criteria. Human users are reviewed for current role, manager approval, and employment status. Service accounts should be reviewed for application ownership, system dependency, last-use evidence, secret rotation status, and whether the account can be replaced with a shorter-lived workload identity. That is the key distinction: the review is shared, but the decision logic is not identical.

Current guidance suggests pairing governance reviews with inventory and telemetry, because a service account that "has an owner" is still risky if no one can explain what it does or when it last authenticated. The NHI Lifecycle Management Guide is useful here because lifecycle visibility, rotation, and offboarding must be assessed together, not as separate tasks. For broader control design, the 52 NHI Breaches Analysis shows how service accounts often become persistent footholds when entitlement review is disconnected from credential hygiene.

• Require a named business or technical owner for every service account.
• Confirm whether the account is tied to a live workload, not just an inherited system.
• Check privilege scope, secret age, and last authentication activity together.
• Use JIT or ephemeral alternatives where the workload can support them.
• Retire accounts that exist only because no one has validated their dependency.

For implementation, align the review to evidence from identity inventory, secrets management, and PAM tooling rather than relying on spreadsheet attestations alone. These controls tend to break down in highly dynamic CI/CD and multi-cloud environments because ownership changes faster than access records do.

Common Variations and Edge Cases

Tighter review requirements often increase operational overhead, requiring organisations to balance governance accuracy against service disruption risk. That tradeoff matters most for legacy systems, shared integrations, and vendor-managed accounts where the business owner cannot easily explain technical necessity but still depends on the workload. In those cases, current guidance suggests a compensating-control approach rather than blind removal.

One common edge case is an account that is technically a service account but behaves like a privileged operator identity. Another is an application account that supports batch jobs, scheduled tasks, or API calls across environments. These should still be reviewed, but the reviewer needs evidence of workload function, not a human supervisor approval chain. The Ultimate Guide to NHIs — Key Challenges and Risks is relevant because excessive privileges, weak visibility, and poor rotation are common failure modes across these variations.

There is no universal standard for this yet, but best practice is evolving toward workload-aware reviews, shorter credential lifetimes, and explicit exceptions for break-glass or vendor-supported accounts. Security teams should avoid judging service accounts by human employment logic alone, because the real question is whether the machine identity still has a justified, bounded purpose.

Related resources from NHI Mgmt Group

• Should organisations treat autonomous agents like human users or service accounts?
• What breaks when organisations manage service accounts like human users?
• How should security teams run access reviews for non-human identities?
• Should organisations treat service accounts like user accounts in Dynamics controls?