{"id":"CVE-2026-4740","revision":"a90e13b0cda54541a18bb0007a67a440","records":[{"revision":"a90e13b0cda54541a18bb0007a67a440","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-4740","aliases":[],"title":"Rhacm: open cluster management (ocm): cross-cluster privilege escalation via improper kubernetes client certificate renewal validation","description":"A flaw was found in Open Cluster Management (OCM), the technology underlying Red Hat Advanced Cluster Management (ACM). Improper validation of Kubernetes client certificate renewal allows a managed cluster administrator to forge a client certificate that can be approved by the OCM controller. 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3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H","score":8.2,"severity":"HIGH"}],"references":["https://access.redhat.com/errata/RHSA-2026:11414","https://access.redhat.com/errata/RHSA-2026:13542","https://access.redhat.com/errata/RHSA-2026:13853","https://access.redhat.com/errata/RHSA-2026:8218","https://access.redhat.com/errata/RHSA-2026:9848","https://access.redhat.com/security/cve/CVE-2026-4740","https://blog.arfevrier.fr/open-cluster-management-cross-cluster-escape/","https://bugzilla.redhat.com/show_bug.cgi?id=2450590"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-4740","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-4740","identifiers":["CVE-2026-4740"]},"retained":false,"historicalAffected":[]}],"coverage":[]}