{"id":"EUVD-2026-19690","revision":"b22b8719b9e3444fb6f732f85c88ebc7","records":[{"revision":"b22b8719b9e3444fb6f732f85c88ebc7","observedAt":"2026-10-28T06:17:50.164+00:00","statement":{"source":"euvd","id":"EUVD-2026-19690","aliases":["CVE-2026-4740","GHSA-q4gv-pjmh-c735"],"title":"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 ce…","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. This enables cross-cluster privilege escalation and may allow an attacker to gain control over other managed clusters, including the hub cluster.","state":0,"publishedAt":null,"modifiedAt":null,"affected":[],"metrics":[{"system":"EUVD CVSS 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":null}],"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://euvd.enisa.europa.eu/vulnerability/EUVD-2026-19690","license":"ENISA EUVD · source terms and attribution apply","enrichment":{"sourceStatus":null,"weaknesses":[],"productCriteria":[],"sourceDates":{"datePublished":"Apr 7, 2026, 2:30:36 PM","dateUpdated":"Sep 9, 2026, 12:04:44 PM"},"relatedAdvisories":[{"id":"RHSA-2026:9848","title":"Red Hat Security Advisory: multicluster engine for Kubernetes v2.6.10 security update","vulnerabilityIds":["CVE-2025-13465","CVE-2025-61726","CVE-2025-61729","CVE-2025-68121","CVE-2026-4740","CVE-2026-22029","CVE-2026-25639","CVE-2026-29063"]},{"id":"RHSA-2026:8218","title":"Red Hat Security Advisory: multicluster engine for Kubernetes v2.8.5 security update","vulnerabilityIds":["CVE-2025-13465","CVE-2025-47907","CVE-2025-58183","CVE-2025-61726","CVE-2025-61729","CVE-2025-68121","CVE-2026-4740","CVE-2026-22029","CVE-2026-25639","CVE-2026-29063"]},{"id":"RHSA-2026:13542","title":"Red Hat Security Advisory: multicluster engine for Kubernetes v2.10.2 security update","vulnerabilityIds":["CVE-2025-13465","CVE-2025-58183","CVE-2025-61726","CVE-2025-61729","CVE-2025-68121","CVE-2026-4740","CVE-2026-22029","CVE-2026-25639","CVE-2026-29063","CVE-2026-40175"]},{"id":"RHSA-2026:13853","title":"Red Hat Security Advisory: multicluster engine for Kubernetes v2.11.1 security update","vulnerabilityIds":["CVE-2026-4740","CVE-2026-29063"]},{"id":"RHSA-2026:11414","title":"Red Hat Security Advisory: multicluster engine for Kubernetes v2.9.3 security update","vulnerabilityIds":["CVE-2025-13465","CVE-2025-61726","CVE-2025-68121","CVE-2026-4740","CVE-2026-25639","CVE-2026-29063","CVE-2026-40175"]}],"note":"EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON."},"key":"euvd:EUVD-2026-19690","identifiers":["EUVD-2026-19690","CVE-2026-4740","GHSA-q4gv-pjmh-c735"]},"retained":false,"historicalAffected":[]}],"coverage":[]}