CVE-2026-17107
Medium
Elevated severity or exploit probability.
CVSS base
8.5
HIGH
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS — probability of exploitation (30 days)
0.6%
44.7th percentile
CISA KEV
Not listed
Weakness / dates
CWE-441
Published 2026-07-24 · modified 2026-09-08
Description
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.
References
- https://access.redhat.com/errata/RHSA-2026:46885
- https://access.redhat.com/errata/RHSA-2026:47388
- https://access.redhat.com/errata/RHSA-2026:47735
- https://access.redhat.com/errata/RHSA-2026:47949
- https://access.redhat.com/errata/RHSA-2026:47953
- https://access.redhat.com/errata/RHSA-2026:47974
- https://access.redhat.com/errata/RHSA-2026:48284
- https://access.redhat.com/security/cve/CVE-2026-17107
- https://bugzilla.redhat.com/show_bug.cgi?id=2506771