Who is accountable when third-party or machine access is over-privileged?

Why This Matters for Security Teams

Over-privileged third-party and machine access is not just an access review issue. It is an accountability failure that turns ordinary entitlements into hidden operational risk. When service accounts, API keys, and vendor connections remain active without a clear owner, teams lose the ability to answer a basic question: who can justify this access today, and who must remove it tomorrow?

That gap is common because non-human access is often created for delivery speed, then left outside normal governance. NHI Mgmt Group research shows that 97% of NHIs carry excessive privileges, and 92% of organisations expose NHIs to third parties, which makes unmanaged sprawl a supply chain problem as much as an internal one. The Ultimate Guide to NHIs is clear that identity ownership, rotation, and offboarding must be treated as core control functions, not optional hygiene.

Current guidance from the OWASP Non-Human Identity Top 10 aligns with the same conclusion: if access has no named business owner and no technical custodian, it is already drifting outside policy. In practice, many security teams discover that drift only after a vendor breach, a failed audit, or a secrets leak has already exposed the entitlement.

How It Works in Practice

Accountability for over-privileged access should be split across three functions, but not diffused across them. The business owner determines why the access exists and whether the use case still justifies the risk. The system owner controls the application, workload, or integration that consumes the entitlement. The identity governance function enforces review cadence, evidence, and removal paths when the business case expires.

Operationally, that means every third-party account, API key, service account, and automation token should be tied to a recorded purpose, an owning team, and an expiry or review date. For mature programmes, this is enforced through lifecycle controls: approval at issuance, periodic recertification, continuous visibility, and deprovisioning when the task ends. NHI Mgmt Group’s Ultimate Guide to NHIs — Key Challenges and Risks shows why this matters: long-lived secrets, poor visibility, and weak offboarding are the conditions that allow over-privilege to persist.

• Assign one accountable business owner per entitlement, even when multiple teams use it.
• Record the system or workload that consumes the access, not just the person who requested it.
• Apply least privilege and remove entitlements that are only needed for setup, migration, or testing.
• Use short-lived credentials where possible and revoke them automatically when the task finishes.
• Require evidence for recertification, including logs, usage history, and current business justification.

The most effective control is not a quarterly spreadsheet review; it is a live ownership model backed by policy and telemetry. These controls tend to break down in distributed SaaS estates where vendors can create nested privileges faster than internal teams can reconcile ownership.

Common Variations and Edge Cases

Tighter ownership controls often increase administrative overhead, so organisations have to balance speed against auditability. That tradeoff becomes sharper when access is used by external partners, CI/CD pipelines, or shared platform services, because the business owner may not directly operate the account that holds the privilege.

Best practice is evolving for these edge cases, but current guidance suggests that ownership should still be explicit even when execution is delegated. For example, a third-party integrator can administer a workload, but the enterprise still owns the entitlement risk and must retain revocation authority. Likewise, machine-to-machine access should not be exempted simply because no human logs in interactively. The identity still has a lifecycle, and the entitlement still requires a named approver and reviewer.

This is where the broader NHI evidence base matters. The 52 NHI Breaches Analysis shows how quickly neglected machine access becomes an incident driver, especially when secrets are reused, shared, or embedded in automation. For teams trying to improve governance, the question is not whether the access is human or non-human. The question is whether someone can still defend it, review it, and remove it on time.

Related resources from NHI Mgmt Group

• When should organisations treat third-party SaaS access as privileged access?
• Who is accountable when a third party keeps access after the work ends?
• Who is accountable when third-party access to PHI is overbroad or unreviewed?
• What breaks when third-party access is not reviewed continuously?