How should security teams govern hidden identities inside application estates?

Start by inventorying every application that issues or consumes identity, then map where authentication and authorisation actually occur. The key is to govern runtime enforcement, not just directory records. That means local accounts, embedded secrets, fallback login paths, and application-side roles all belong in the control scope.

Why This Matters for Security Teams

Hidden identities are the credentials and accounts that security teams do not see in a directory review, but that applications still trust at runtime. They include local service accounts, embedded API keys, cached tokens, fallback login paths, and application-side roles. This matters because attackers usually do not need to break the primary identity system if they can find one trusted path inside the application estate.

NHI Management Group’s research shows how often these identities escape operational control: only 5.7% of organisations have full visibility into their service accounts, and 80% of identity breaches involved compromised non-human identities such as service accounts and API keys. The issue is not only inventory, but enforcement. Teams that govern records while ignoring runtime authorisation are often looking at the wrong control plane. Guidance in the Ultimate Guide to NHIs and the NIST Cybersecurity Framework 2.0 both point toward visibility, governance, and continuous control rather than static registration alone.

In practice, many security teams encounter hidden identity abuse only after a breach review reveals that an application had more trust paths than its owners documented.

How It Works in Practice

Effective governance starts by treating each application as an identity issuer, identity consumer, or both. That means mapping where authentication is created, where tokens are stored, where authorisation is enforced, and where privileged actions can still be reached if the primary control fails. The goal is not just to enumerate accounts, but to understand which identities can still act when a directory record looks clean.

Security teams typically build this control view across four layers:

• Discovery of local accounts, service principals, OAuth apps, API keys, and machine credentials.
• Mapping of fallback paths such as hard-coded admins, shared accounts, and bypass roles.
• Runtime policy review for application-side authorisation, including role checks, token scope, and session context.
• Lifecycle controls for issuance, rotation, revocation, and offboarding tied to application ownership.

This is where Top 10 NHI Issues becomes useful: many high-risk patterns are not exotic, they are mundane secrets spread across code, CI/CD, and integration layers. The control objective should align with NIST SP 800-53 Rev. 5 Security and Privacy Controls by tying access enforcement to least privilege, account management, and continuous monitoring. For large estates, current guidance suggests separating inventory work from enforcement work so owners can fix the identity at the place it is actually used.

These controls tend to break down when applications are deployed through many unmanaged pipelines because the identity source, secret storage, and policy decision all change faster than the security review cycle.

Common Variations and Edge Cases

Tighter identity governance often increases operational overhead, requiring organisations to balance risk reduction against application friction and release speed. That tradeoff is especially visible in legacy systems, where local accounts and embedded credentials may be the only stable path for business-critical workflows.

There is no universal standard for every edge case, but current guidance suggests treating exceptions explicitly rather than letting them become permanent. Common examples include vendor-managed applications, batch jobs, service-to-service integrations, and plugins that issue their own credentials. In each case, the hidden identity should have an owner, an expiry expectation, a revocation path, and a monitoring rule. If an application cannot support these basics, it should be flagged as an identity governance exception, not silently accepted.

Security teams also need to account for shadow paths created outside central IAM, such as temporary admin accounts used during migrations or secrets copied into build tooling. The Ultimate Guide to NHIs – Regulatory and Audit Perspectives is a practical reference for showing why auditors care about traceability, not just policy intent. Hidden identities are easiest to miss in environments with frequent mergers, multi-cloud sprawl, or app teams that can change auth logic without security review.

Related resources from NHI Mgmt Group

• How should security teams decide whether JIT access is safe for non-human identities?
• How should IAM teams govern application identities that are hidden in code and runtime flows?
• How should security teams govern non-human identities at scale?
• How should security teams govern non-human identities for compliance?