They complicate reviews because they often sit outside normal employee processes, change hands without clear ownership, and remain active after the original need has ended. That creates audit gaps, unclear accountability, and hidden privilege. Compliance teams need the same lifecycle discipline for these identities that they already expect for human access.
Why This Matters for Security Teams
service account and third-party identities are hard to review because they do not follow the same ownership and approval patterns as employees. They are often created for platforms, vendors, pipelines, or integrations, then reused quietly across teams. That makes it easy for access to outlive the business justification, especially when the original requester has left, the vendor relationship changed, or the system was copied into a new environment.
This is where compliance and security start to diverge if identity lifecycle discipline is weak. The issue is not just “too many accounts”; it is that these identities frequently lack reliable evidence for who approved them, who owns them today, and when they should be removed. NHIMG research shows that Ultimate Guide to NHIs — Regulatory and Audit Perspectives frames this as a governance problem, while the OWASP Non-Human Identity Top 10 treats visibility, lifecycle, and privilege as core risk themes. In practice, many teams only discover the gap when an auditor asks for evidence and the record trail is incomplete.
That matters because compromised or forgotten service identities can still move data, call APIs, and retain standing privileges long after the business need has ended.
How It Works in Practice
A strong review process treats these identities as first-class assets, not exceptions to employee IAM. Start with a complete inventory of service accounts, API keys, tokens, certificates, and third-party identities, then tie each one to a named owner, a business purpose, and a renewal date. The Ultimate Guide to NHIs — Lifecycle Processes for Managing NHIs and the NIST Cybersecurity Framework 2.0 both support this lifecycle view: identify, govern, review, and retire access continuously rather than only during annual certification.
For compliance reviews, the practical evidence set should include:
- who requested the identity and who approved it;
- what system, vendor, or workload it serves;
- what privileges it has, including any admin or cross-environment access;
- when credentials or secrets were last rotated;
- how deprovisioning is triggered when the contract, service, or pipeline ends.
That evidence becomes more defensible when access is narrowed with RBAC, PAM, and JIT provisioning, and when secrets are short-lived rather than permanently embedded in code or config. Where third parties are involved, current guidance suggests requiring explicit contract language for access ownership, logging, and offboarding, because “vendor managed” does not mean “compliance exempt.” NHIMG’s breach research, including 52 NHI Breaches Analysis, shows why stale secrets and hidden privilege keep resurfacing as audit findings. Organisations should also assume that secrets can leak through CI/CD, ticketing, or shared tooling unless those channels are controlled end to end.
These controls tend to break down in highly automated environments with inherited cloud roles and unmanaged vendor integrations, because ownership, revocation, and evidence collection are no longer tied to a single system of record.
Common Variations and Edge Cases
Tighter review controls often increase operational overhead, so organisations need to balance auditability against deployment speed and partner friction. That tradeoff becomes sharper with short-lived jobs, ephemeral containers, and managed services where a human reviewer cannot inspect every access event in advance.
There is no universal standard for this yet, but best practice is evolving toward context-aware review. That means looking at the identity’s actual usage patterns, the blast radius of its permissions, and whether the access can be reduced to a workload identity instead of a shared secret. In cloud-native stacks, a service account tied to an autoscaling job may need JIT credentials for minutes rather than days. In third-party scenarios, the review should ask whether the external party needs direct access at all, or whether a brokered integration with intent-based authorisation would lower risk.
Two patterns create recurring exceptions. First, “break glass” service identities may legitimately retain broad rights, but those exceptions need explicit expiry, monitoring, and post-use review. Second, legacy vendor connectors may not support modern controls such as OIDC, SPIFFE/SPIRE-style workload identity, or real-time policy evaluation. In those cases, compensating controls should be documented rather than assuming the risk is acceptable by default. The Top 10 NHI Issues and the NIST Cybersecurity Framework 2.0 both reinforce the same principle: if the identity can act, it must be reviewable, accountable, and removable.
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 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 | NHI-03 | Rotation and lifecycle control are central to service account review gaps. |
| NIST CSF 2.0 | PR.AC-4 | Least-privilege access reviews apply directly to non-human identities. |
| NIST Zero Trust (SP 800-207) | Zero Trust requires continuous verification of non-human identity access. |
Treat each non-human request as untrusted until policy, context, and ownership are validated.
