Why do privileged account inventories keep growing even when PAM tools are in place?

Because discovery and enforcement are not the same thing. Tools can identify accounts, but without a decision layer they do not tell teams whether an account should be vaulted, converted to JIT, placed under secret management, or removed. Inventory growth continues when lifecycle decisions are deferred or inconsistent.

Why This Matters for Security Teams

Privileged account inventories keep expanding when teams confuse discovery with governance. PAM platforms can surface service accounts, shared admin logins, API keys, and certificates, but visibility alone does not answer the operational question: what should happen to each identity next? That gap is why inventories swell even after tool rollout. NHI Management Group’s Ultimate Guide to NHIs — Key Challenges and Risks notes that 97% of NHIs carry excessive privileges, which shows how often accounts are found but not truly governed.

This issue is bigger than cleanup. Once a privileged non-human identity is exempted “for now,” it often remains in place because no one owns the lifecycle decision to vault it, convert it to JIT, rotate it, or retire it. That is especially common in environments with inherited accounts, application-to-application access, and exception-heavy change processes. The industry guidance in the OWASP Non-Human Identity Top 10 is clear that unmanaged machine identities create persistent exposure, not just visibility gaps. In practice, many security teams encounter inventory sprawl only after a failed audit, an incident review, or a renewal cycle that never resulted in removal.

How It Works in Practice

A mature program treats privileged inventory as a decision workflow, not a static register. Discovery should feed a triage path that classifies each account by function, owner, privilege level, expiry, and dependency. From there, the team decides whether the identity belongs in a vault, should be wrapped in just-in-time controls, needs secret manager migration, or is a deletion candidate. NIST’s SP 800-53 Rev. 5 Security and Privacy Controls supports this model through access control, account management, and auditability expectations, but the controls only work when applied to a defined lifecycle.

In practice, teams reduce growth by forcing a decision at intake and at every review. Useful steps include:

• Map each privileged account to a named business owner and technical custodian.
• Classify whether the account is human-operated, application-bound, or ephemeral workload identity.
• Set a default disposition: rotate, vault, convert to JIT, or decommission.
• Require expiry dates for exceptions and revisit them on a fixed cadence.
• Track accounts that cannot be removed because of application coupling or vendor dependency.

NHIMG’s NHI Lifecycle Management Guide is relevant here because lifecycle governance is where inventory reduction actually happens. Discovery tells a team what exists; lifecycle discipline decides what continues to exist. These controls tend to break down in legacy environments where shared credentials are embedded in code, tied to brittle vendor integrations, or owned by no single application team.

Common Variations and Edge Cases

Tighter inventory controls often increase operational overhead, requiring organisations to balance reduction goals against uptime, release speed, and support burden. That tradeoff is real, especially where system owners fear breaking automation or where regulated production systems cannot tolerate frequent credential changes. In those environments, best practice is evolving rather than universal: some teams keep a small number of long-lived exceptions, but only with explicit risk acceptance, strong monitoring, and documented review dates.

Another edge case is the “shadow privileged account” problem. A PAM tool may know the account exists, but the application may also hold a cached token, an embedded certificate, or a parallel API key outside the vault. The inventory appears stable while the real privilege surface keeps expanding. That is why NHI programs often pair PAM with secret discovery and offboarding controls, rather than treating PAM as the whole answer. The NHI Management Group article on the Top 10 NHI Issues is a useful reminder that lifecycle gaps and excessive privilege usually travel together.

For boards and audit teams, the practical metric is not how many accounts were discovered. It is how many were classified, remediated, or removed within a defined SLA. Without that second step, inventories will keep growing even in well-funded PAM environments.

Related resources from NHI Mgmt Group

• How should security teams keep privileged account inventories current in mature PAM programs?
• What should IAM teams do when employees keep using unsanctioned AI tools?
• Why do non-human identities create compliance risk even when policies exist?
• Why do collaboration tools create such a large secrets risk?