open-cluster-management-io/ocm · Security
Open Cluster Management (OCM): Cross-cluster privilege escalation via improper Kubernetes client certificate renewal validation
- GHSA ID
- GHSA-q4gv-pjmh-c735
- CVE ID
- CVE-2026-4740
- Severity
- high
- Published
- Updated
- CVSS
- 8.2 · CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
- CVSS v3
- 8.2 · CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
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.
CWEs
- CWE-295 · Improper Certificate Validation
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-4740 ↗
- 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 ↗
- https://github.com/open-cluster-management-io/ocm/commit/9e70cc1e21a15239c81111062c0b37df4b5a8026 ↗
- https://github.com/advisories/GHSA-q4gv-pjmh-c735 ↗