Long-lived API keys increase NHI risk because every extra day of validity gives an exposed credential more opportunity to be copied, reused, or discovered by an attacker. Service accounts and tokens often move through code and tooling that were not designed for manual retirement. The longer the key lives, the harder it is to trust that it is still safe.
Why This Matters for Security Teams
Long-lived api key are not just a hygiene problem, they are an exposure multiplier. Every extra day a secret remains valid increases the chance it will be copied into source control, embedded in CI/CD logs, shared across tools, or discovered during an incident. NHI risk rises because service accounts and automation tokens are often created for speed, then forgotten until they become a standing path into production. That pattern is exactly why NHI guidance prioritises lifecycle control, visibility, and rotation in the Ultimate Guide to NHIs.
The scale of the problem is not theoretical. NHIMG research shows 71% of NHIs are not rotated within recommended time frames, and 30.9% of organisations store long-term credentials directly in code. That combination means a single leaked key can remain useful long after the original deployment event has passed. Current guidance from the NIST Cybersecurity Framework 2.0 still points teams toward strong governance, but the operational challenge is that API keys are often treated as set-and-forget artefacts rather than governed identities. In practice, many security teams discover this only after a forgotten credential has already been reused outside its intended system.
How It Works in Practice
A long-lived key increases risk because it widens the window in which an attacker can exploit it, and it weakens the team’s ability to prove the secret is still legitimate. If a token is valid for months, there are many more opportunities for theft, replay, and accidental propagation. This is especially dangerous when the key is tied to a service account with broad privileges, because the secret becomes a durable proxy for the workload itself. The attack pattern is familiar in breaches involving exposed machine credentials, including cases documented in Cisco DevHub NHI breach and 52 NHI Breaches Analysis.
Practitioners reduce this risk by replacing static, durable secrets with shorter-lived controls and better identity proof. That usually means:
- Use JIT credential provisioning so access exists only for the task and is revoked automatically on completion.
- Prefer workload identity and short-lived tokens over shared API keys, so the credential proves what the workload is rather than what a person remembers.
- Bind secrets to context, such as environment, workload, or request path, instead of reusing one key everywhere.
- Rotate or revoke credentials immediately when ownership changes, code changes, or a leak is suspected.
- Store secrets in dedicated secret managers rather than code, config files, or CI/CD variables.
That approach aligns with the NIST view that access should be intentionally controlled, but it also reflects the reality captured in the Ultimate Guide to NHIs — What are Non-Human Identities, where secrets hygiene and offboarding remain weak across many environments. These controls tend to break down when legacy applications require hard-coded keys and there is no reliable automation for rotation or dependency discovery.
Common Variations and Edge Cases
Tighter secret lifetimes often increase operational overhead, requiring organisations to balance security benefit against deployment complexity. That tradeoff is real in embedded systems, partner integrations, and older workloads that cannot easily fetch ephemeral credentials. In those environments, current guidance suggests compensating with stronger monitoring, narrower privileges, and more frequent review rather than assuming the static key is harmless just because it is hard to replace.
There is no universal standard for every exception, but the direction is clear: minimise the number of keys that ever need to live for a long time. Where long-lived credentials are unavoidable, they should be isolated, documented, and placed under explicit ownership with regular revalidation. The Top 10 NHI Issues and Guide to the Secret Sprawl Challenge both reflect the same operational reality: secret sprawl turns a simple access mechanism into a durable blast radius. For teams aligning governance, the right mental model is not “how long can this key survive” but “how quickly can this identity be replaced without breaking the service.” That is the point where NHI risk starts to fall instead of accumulate.
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 AI RMF set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-03 | Long-lived secrets increase exposure and weaken rotation discipline. |
| NIST CSF 2.0 | PR.AC-4 | Least-privilege access controls reduce damage from leaked API keys. |
| NIST AI RMF | AI risk governance supports accountability for autonomous credential use. |
Assign ownership for machine identities and govern their lifecycle end to end.
Related resources from NHI Mgmt Group
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Reviewed and updated by the NHIMG editorial team on June 1, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
