Set Short-Lived Machine Credentials
Choose short-lived machine credentials where supported, and test renewal, expiry, failure, and emergency fallback paths.
A long-lived static key can remain useful after it is copied. A short-lived machine credential narrows the time window, but only if issuance, renewal, and revocation work reliably. Do not replace a stable key with an expiring token until the workload can recover from provider outages and clock drift.
Inspect the provider's supported methods: workload identity, OAuth client credentials, signed assertions, or static keys. OWASP's secrets guidance favors controlled lifecycle management. Choose the shortest workable lifetime based on real job duration and renewal behavior, not a universal number copied from another service.
Credential choice table
| Workload question | Decision to record |
|---|---|
| Identity source | Which platform proves the machine identity? |
| Audience | Which service will accept the token? |
| Scope | Which actions and resources are needed? |
| Lifetime | How long must one task run? |
| Renewal | Who obtains a fresh credential and when? |
| Outage mode | Stop, retry, or use approved fallback? |
| Revocation | How can the issuer end access early? |
Keep the credential in a broker or platform identity service. The agent or application should ask for an operation, not handle a token directly. Cache only as long as necessary. A refresh failure must not cause a fallback to a broader permanent key without a documented operator decision.
Failure rehearsal
In an owned environment, start a normal job and confirm it succeeds with a fresh credential. Expire the token before another call and check that the client renews it once, without logging it. Revoke the machine identity and confirm new issuance stops. Test an issuer outage and a clock-skew case. The workload should fail safely or use a specifically approved fallback.
Synthetic renewal decision
| Event | Expected observation | Decision |
|---|---|---|
| Fresh token for service A | Owned read succeeds | Continue |
| Token for service B | A rejects before work | Fix audience binding |
| Expired token | One protected renewal, then owned read | Continue only if renewal succeeds |
| Issuer unavailable | No new broad static key is used | Hold or use a separately approved fallback |
Record event time, response class, and job health without token bytes. If the provider cannot issue short-lived credentials, keep the static key on a named review with tighter scope and rotation.
Make offboarding verifiable
Use the offboarding checklist to identify owners, revoke grants and verify the result. Discuss a scoped review of your application's access controls.
Sources
- OWASP Secrets Management Cheat SheetAccessed
- OWASP OAuth2 Cheat SheetAccessed