{"id":"CVE-2026-4740","sourceIdentifier":"secalert@redhat.com","published":"2026-04-07T15:17:46.797","lastModified":"2026-10-26T21:10:00.170","vulnStatus":"Modified","cveTags":[],"descriptions":[{"lang":"en","value":"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. This enables cross-cluster privilege escalation and may allow an attacker to gain control over other managed clusters, including the hub cluster."},{"lang":"es","value":"Se encontró una vulnerabilidad en Open Cluster Management (OCM), la tecnología subyacente a Red Hat Advanced Cluster Management (ACM). Una validación incorrecta de la renovación de certificados de cliente de Kubernetes permite a un administrador de clúster gestionado forjar un certificado de cliente que puede ser aprobado por el controlador de OCM. Esto permite la escalada de privilegios entre clústeres y puede permitir a un atacante obtener control sobre otros clústeres gestionados, incluyendo el clúster central."}],"affected":[{"source":"secalert@redhat.com","affectedData":[{"vendor":"Red Hat","product":"multicluster engine for Kubernetes 2.1","defaultStatus":"affected","collectionURL":"https://catalog.redhat.com/software/containers/","packageName":"multicluster-engine/registration-rhel9","cpes":["cpe:/a:redhat:multicluster_engine:2.10::el9"],"versions":[{"version":"1776881164","lessThan":"*","versionType":"rpm","status":"unaffected"}]},{"vendor":"Red Hat","product":"multicluster engine for Kubernetes 2.11","defaultStatus":"affected","collectionURL":"https://catalog.redhat.com/software/containers/","packageName":"multicluster-engine/registration-rhel9","cpes":["cpe:/a:redhat:multicluster_engine:2.11::el9"],"versions":[{"version":"1777478390","lessThan":"*","versionType":"rpm","status":"unaffected"}]},{"vendor":"Red 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