CVE-2026-17107
Cluster-proxy: impersonation-header injection grants cluster-admin on every managed cluster
HIGH 8.5
At a glance
- Source
- NVD
- EPSS
- EPSS 0.57 % · percentile 47 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- redhat
- NVD status
- Awaiting Analysis
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.
Weaknesses (CWE)
- CWE-441 — Unintended Proxy or Intermediary
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
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 8.5 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H | redhat |
| CVSS 3.1 | HIGH 8.5 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H | NVD · secalert@redhat.com (Secondary) |
European references
- ENISA EUVD · EUVD-2026-48728
- GCVE · GCVE-0-2026-17107
Affected products
| Product | Versions |
|---|---|
| Red Hat · multicluster engine for Kubernetes 2.10 | unaffected 1784342329 < * |
| Red Hat · multicluster engine for Kubernetes 2.10 | unaffected 1784342329 < * |
| Red Hat · multicluster engine for Kubernetes 2.11 | unaffected 1784925025 < * |
| Red Hat · multicluster engine for Kubernetes 2.17 | unaffected 1784926298 < * |
| Red Hat · multicluster engine for Kubernetes 2.6 | unaffected 1783985960 < * |
| Red Hat · multicluster engine for Kubernetes 2.8 | unaffected 1784342329 < * |
| Red Hat · multicluster engine for Kubernetes 2.9 | unaffected 1783278220 < * |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |