CVE-2026-73266 [HIGH] – A flaw was found in the clusterclaims-controller component of Multicluster Engine (MCE). A

A flaw was found in the clusterclaims-controller component of Multicluster Engine (MCE). An authenticated tenant can exploit this vulnerability by manipulating ClusterClaim labels. This allows the tenant to force a cluster to join a ManagedClusterSet belonging to another tenant. Such unauthorized access could enable the injection of policies and workloads into other tenants’ clusters.