Cluster-proxy: cluster-proxy: impersonation header injection in service-proxy grants cluster-admin on every managed cluster
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.5epss 0.3%
exploitation probability
0.3%top 73% of all CVEs
observed exploitation
nono source reports it
A flaw was found in the cluster-proxy service-proxy component used in Red Hat Advanced Cluster Management for Kubernetes (RHACM) and multicluster-engine (MCE). The service-proxy appends impersonation group headers to proxied requests without first removing caller-supplied values, and the spoke ServiceAccount holds unrestricted impersonation permissions. An authenticated hub principal can inject an Impersonate-Group header to escalate to cluster-admin on every managed cluster.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Affected products
Red Hat · multicluster engine for Kubernetes 2.10Red Hat · multicluster engine for Kubernetes 2.11Red Hat · multicluster engine for Kubernetes 2.17Red Hat · multicluster engine for Kubernetes 2.6Red Hat · multicluster engine for Kubernetes 2.8Red Hat · multicluster engine for Kubernetes 2.9References
https://access.redhat.com/errata/RHSA-2026:46885https://access.redhat.com/errata/RHSA-2026:47388https://access.redhat.com/errata/RHSA-2026:47735https://access.redhat.com/errata/RHSA-2026:47949https://access.redhat.com/errata/RHSA-2026:47953https://access.redhat.com/errata/RHSA-2026:47974https://access.redhat.com/errata/RHSA-2026:48284https://access.redhat.com/security/cve/CVE-2026-17107https://bugzilla.redhat.com/show_bug.cgi?id=2506771