{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-16652", "assignerOrgId": "61241ed8-fa44-4f23-92db-b8c443751968", "state": "PUBLISHED", "assignerShortName": "Temporal", "dateReserved": "2026-07-22T18:08:55.806Z", "datePublished": "2026-09-21T11:23:47.298Z", "dateUpdated": "2026-09-21T15:33:15.387Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "61241ed8-fa44-4f23-92db-b8c443751968", "shortName": "Temporal", "dateUpdated": "2026-09-21T11:23:47.298Z"}, "title": "Temporal Server Schedule exclusion search can cause excessive CPU consumption", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-606", "description": "CWE-606: Unchecked Input for Loop Condition", "type": "CWE"}]}], "impacts": [{"descriptions": [{"lang": "en", "value": "Availability degradation or denial of service caused by excessive CPU consumption and a persistent Schedule retry condition. 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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.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<p>Temporal Server did not bound the work performed while searching for a Schedule's next action time. 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