Yes, when certificates are used to authenticate services, APIs, workloads, or automation, they function as non-human credentials and should be governed as such. Folding them into NHI programmes improves lifecycle control, ownership, and offboarding discipline. It also avoids the common failure mode where machine trust is managed as infrastructure rather than identity.
Why This Matters for Security Teams
Certificates are often treated as technical plumbing, but in practice they are bearer-style credentials with an identity function. If a certificate can authenticate a workload, API, service account, or automation flow, then its issuance, ownership, rotation, revocation, and expiry are security decisions, not just infrastructure tasks. That is why folding certificates into an NHI programme is a governance choice as much as an operational one. The NIST Cybersecurity Framework 2.0 frames this well through outcomes tied to asset visibility, access control, and risk management.
The risk is not limited to expired certificates. Weak ownership models create invisible trust paths that survive staff changes, platform migrations, and emergency fixes. Security teams then inherit certificates that no one can confidently approve, rotate, or decommission. In NHI terms, that is the same control failure seen with unmanaged secrets: no accountable owner, no lifecycle policy, and no reliable inventory. In practice, many security teams encounter certificate misuse only after an outage, audit finding, or incident has already exposed unmanaged trust paths, rather than through intentional identity governance.
How It Works in Practice
Operationally, certificates should be classified by use case and trust boundary. A certificate that authenticates a production workload, mTLS connection, CI/CD runner, or internal API should sit in the same governance model as other non-human credentials. That means assigning ownership, naming the business or technical service it represents, defining issuance authority, and linking it to a revocation path.
- Inventory certificates alongside other NHIs, not just in infrastructure tooling.
- Map each certificate to a service owner, system owner, or automation owner.
- Define renewal, rotation, and revocation thresholds before expiry creates outage risk.
- Separate short-lived operational certificates from long-lived trust anchors and document the difference.
- Log issuance and revocation events into SIEM or certificate management monitoring where feasible.
Security and platform teams should also distinguish certificate-based authentication from certificate storage. A certificate may be embedded in a container image, delivered by a secrets manager, or issued dynamically by a trust service. The governance question remains the same: who owns it, what does it authenticate, and what happens when the workload changes? Guidance from the OWASP Secrets Management Cheat Sheet is useful here because certificates are operationally similar to other sensitive credentials even when they are not password-like.
Where mature programmes exist, certificate lifecycle events are integrated into onboarding, change management, and decommissioning processes. That creates a cleaner link between identity governance and operational resilience. Current guidance suggests this is especially important in cloud-native environments where service identity changes rapidly and certificate sprawl is common. These controls tend to break down in highly distributed environments with multiple certificate authorities, because ownership and revocation signals fragment across teams and platforms.
Common Variations and Edge Cases
Tighter certificate governance often increases operational overhead, requiring organisations to balance stronger accountability against renewal friction and platform complexity. That tradeoff is real, especially where certificates are issued at high volume or embedded in ephemeral workloads. Best practice is evolving, and there is no universal standard for whether every certificate must live in a formal NHI catalogue, but the ones that confer authentication or authorisation should be treated as identity-bound credentials.
One edge case is public TLS certificates for websites. These matter for trust, but they do not always belong in the same NHI workflow as internal workload certificates because the ownership model and threat surface differ. Another edge case is transport-only certificates used by managed services where the cloud provider abstracts lifecycle control. Even then, the organisation should still know who is accountable for the service trust chain and how the certificate is monitored.
For environments adopting zero trust or service mesh patterns, certificate governance becomes more important, not less. The NIST Zero Trust Architecture guidance reinforces the need to continuously validate trust rather than assume it. The practical takeaway is simple: if a certificate proves machine identity, it belongs in the same governance conversation as the rest of the non-human identity estate.
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, NIST Zero Trust (SP 800-207), NIST SP 800-63 and NIST AI RMF set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST CSF 2.0 | PR.AA-01 | Certificate identity and access flows support asset and access governance. |
| OWASP Non-Human Identity Top 10 | Certificates are non-human credentials and fit NHI lifecycle governance. | |
| NIST Zero Trust (SP 800-207) | 3.1 | Zero trust requires continuous validation of machine trust and credentials. |
| NIST SP 800-63 | Digital identity principles help frame assurance and lifecycle accountability. | |
| NIST AI RMF | GOVERN-1 | Governance principles apply where certificates secure AI or automated systems. |
Catalogue certificate-bearing services and tie each to an accountable owner and lifecycle process.
