PKI modernisation is the shift from manual, legacy certificate operations to managed, automated, and more visible certificate governance. It matters because the value is not only lower cost, but tighter control over expiry, ownership, and trust boundaries across the environment.
Expanded Definition
PKI modernisation is the move from certificate handling that depends on spreadsheets, ticket queues, and manual renewals to a governed model with automation, discovery, and policy enforcement. In NHI security, the term is usually broader than “certificate automation” because it includes ownership mapping, trust boundary review, issuance standards, revocation readiness, and lifecycle visibility across machines, workloads, and agentic systems.
Definitions vary across vendors, but the security objective is consistent: reduce silent certificate expiry and make trust relationships auditable. Modern programmes typically align PKI with inventory, risk review, and control mapping rather than treating certificates as isolated infrastructure artefacts. That is why guidance from NIST Cybersecurity Framework 2.0 is relevant even when the deployment model is highly specialised.
PKI modernisation is often misunderstood as a tooling refresh only. The most common misapplication is automating renewals without fixing certificate ownership and trust scope, which occurs when teams fail to connect certificates to the systems and services that depend on them.
Examples and Use Cases
Implementing PKI modernisation rigorously often introduces change-control and dependency-mapping overhead, requiring organisations to weigh faster renewal against tighter governance and more complete discovery.
- Replacing ad hoc certificate renewals with automated issuance and rotation for API gateways, service meshes, and internal workloads.
- Building a live certificate inventory so security teams can identify expiry risk before outages affect production services, a need that is common when organisations discover how many NHIs they actually operate in the Ultimate Guide to NHIs.
- Binding certificates to named service owners so revocation, replacement, and incident response have a clear accountability path.
- Using policy to separate trust zones for external partners, third-party integrations, and internal automation, instead of reusing broad certificate trust indiscriminately.
- Aligning issuance and renewal workflows with NIST Cybersecurity Framework 2.0 to strengthen asset visibility and access control.
In mature environments, PKI modernisation also supports migration away from long-lived, manually tracked certificates toward shorter-lived credentials that are easier to monitor and revoke.
Why It Matters in NHI Security
PKI is a core trust mechanism for NHIs, so weak certificate governance can create hidden outage paths and authentication failures across services, workloads, and automation. When certificates are unmanaged, expired, duplicated, or assigned without clear ownership, the result is not just downtime. It is also blind trust expansion, where systems continue relying on credentials nobody can confidently inventory or revoke. That is especially dangerous in environments already struggling with NHI sprawl and visibility gaps.
The NHI Management Group reports that only 5.7% of organisations have full visibility into their service accounts, and that lack of visibility often extends to certificate-backed identities as well. The same governance gap appears in broader credential handling, where 96% of organisations store secrets outside secrets managers in vulnerable locations, according to the Ultimate Guide to NHIs. PKI modernisation gives security teams a way to tie trust to ownership, policy, and lifecycle evidence instead of inherited assumptions. It also supports trust decisions that fit Zero Trust models rather than relying on static network placement.
Organisations typically encounter PKI modernisation as an urgent requirement only after a major certificate expiry or trust failure, at which point certificate governance becomes operationally unavoidable to address.
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 and NIST Zero Trust (SP 800-207) set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-02 | Covers improper secret and credential lifecycle handling, which includes certificate governance gaps. |
| NIST CSF 2.0 | PR.AC-1 | PKI supports identity proofing and access control for machine and workload identities. |
| NIST Zero Trust (SP 800-207) | Zero Trust relies on continuously validated trust relationships, including certificate-based identity. |
Inventory certificates, assign owners, and automate renewal and revocation before expiry becomes an incident.
Related resources from NHI Mgmt Group
- What is the difference between PKI hygiene and machine identity governance?
- When should organisations modernise PKI instead of keeping legacy processes?
- Should organisations prioritise passwordless or privileged access modernisation first?
- Should organisations prioritise internal PKI after automating external certificates?
