Vulnerability in Red Hat Multicluster Engine For Kubernetes
CVE-2026-73266
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (26.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 26th percentile — 26.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.004 · change: +0.001
Affected products
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-73266 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
- access.redhat.com/errata/RHSA-2026:59556 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:59593 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:59557 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:59558 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:59559 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:59579 (vendor-advisory)
Frequently asked questions
- What is CVE-2026-73266?
- CVE-2026-73266 is a high-severity vulnerability in Red Hat Multicluster Engine For Kubernetes, classified under Unintended Proxy or Intermediary (Confused Deputy). CVSS score: 7.1/10. Published 2026-08-13.
- How severe is CVE-2026-73266?
- High severity. CVSS v3 base score is 7.1 out of 10.