Why do third-party vendors complicate identity governance more than internal users?

Why This Matters for Security Teams

Third-party access is harder to govern because it sits outside the normal employment lifecycle. Vendors come and go with contracts, implementation milestones, support windows, and procurement changes, so access must be reviewed against the relationship, not the person. That makes entitlement drift more likely, especially when approvals are reused across projects or when offboarding depends on business owners rather than enforcement. NHI Mgmt Group research shows that 92% of organisations expose NHIs to third parties, which is why this problem often appears first in shared accounts, API keys, and service integrations, not in the HR system. See the Ultimate Guide to NHIs and the NIST Cybersecurity Framework 2.0 for the governance model behind this distinction. In practice, many security teams discover vendor access problems only after a contract ends or a project closes, rather than through intentional access review.

How It Works in Practice

The practical issue is that third-party vendors rarely operate under stable RBAC assumptions. Internal users usually map to job functions, but vendors map to a mix of contract scope, support duties, time-bound deliverables, and exceptions approved by multiple stakeholders. That means access should be handled with tighter lifecycle controls: onboarding tied to a ticket or contract, scoped privileges for a named purpose, time limits where possible, and revocation that is triggered by business events as well as technical signals. Current guidance suggests combining PAM, JIT access, and periodic entitlement recertification so vendors do not retain standing access after the work ends. NHI governance also needs visibility into where secrets are stored and how they are shared. The Ultimate Guide to NHIs — Lifecycle Processes for Managing NHIs and the OWASP Non-Human Identity Top 10 both stress that credential ownership, rotation, and offboarding are as important as initial approval. In operational terms:

• bind access to a service request, contract term, or ticket number;
• replace shared vendor accounts with named identities and strong audit trails;
• issue short-lived secrets or JIT credentials instead of long-lived keys;
• revoke access automatically when the engagement ends or changes scope;
• revalidate privileged access after each renewal, not just at annual review.

This also matters for non-human access created by vendors, because service accounts and API keys often outlive the relationship that created them. The same control gap shows up in breach analysis and lifecycle failures, including the 52 NHI Breaches Analysis and the Top 10 NHI Issues. These controls tend to break down when vendor work is urgent, cross-functional, or embedded in CI/CD pipelines because ownership becomes unclear and revocation is no longer tied to a single system.

Common Variations and Edge Cases

Tighter vendor controls often increase operational overhead, so organisations have to balance speed against assurance. That tradeoff is especially visible in managed services, outsourced development, and emergency support, where access may need to be granted quickly but still remain bounded. Best practice is evolving for these cases, and there is no universal standard for every vendor model yet. Some organisations use break-glass access, but that should be exceptional and monitored, not the default for routine support. Others rely on external identity federation and just-in-time elevation to reduce standing privilege, which works well when the vendor has mature controls of its own. For regulated environments, the question is not only who approved access, but whether the vendor can prove their own offboarding, logging, and secret handling practices. The Ultimate Guide to NHIs — Regulatory and Audit Perspectives and the The 52 NHI breaches Report are useful references when third-party risk intersects with audit evidence. In practice, vendor governance fails most often when contracts renew without a fresh access review, or when a partner keeps machine credentials long after the business owner assumes they were removed.

Related resources from NHI Mgmt Group

• Why do third-party relationships complicate identity and access management?
• Why do service accounts and third-party identities complicate compliance reviews?
• Why do non-human identities complicate identity governance programmes?
• Why do delegated SaaS integrations complicate identity governance?