Vulnerability Description
Temporal Server did not bound the work performed while searching for a Schedule's next action time. An authenticated caller with namespace write permission could create or update a Schedule that combines a fine-grained cadence with an exclusion calendar that rejects every candidate time, causing the server to evaluate excluded candidates without a per-search work budget. This can consume excessive CPU in Frontend and Schedule worker components. A persisted specification can also cause its backing Schedule Workflow to repeatedly fail and retry, allowing CPU consumption to continue without additional requests until the Schedule is deleted or its backing Workflow is terminated. Repeated or parallel exploitation can deny service. The issue affects availability only; it does not expose or modify Workflow data.
Related Weaknesses (CWE)
References
- https://github.com/temporalio/temporal/commit/c10c730e53ae394fffaefe44ba3722150f
- https://github.com/temporalio/temporal/pull/11014
- https://github.com/temporalio/temporal/releases/tag/v1.30.7
- https://github.com/temporalio/temporal/releases/tag/v1.31.3
FAQ
What is CVE-2026-16652?
CVE-2026-16652 is a documented vulnerability. Temporal Server did not bound the work performed while searching for a Schedule's next action time. An authenticated caller with namespace write permission could create or update a Schedule that combi...
How severe is CVE-2026-16652?
CVSS scoring is not yet available for CVE-2026-16652. Check NVD for updates.
Is there a patch for CVE-2026-16652?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.