Vulnerability in Red Hat Multicluster Engine For Kubernetes
CVE-2026-66795
A flaw was found in the managedcluster-import-controller. The Certificate Signing Request (CSR) auto-approval logic improperly validates incoming CSRs, specifically by not inspecting the signer name or decoding the PEM-encoded x509 CSR. This vulnerability allows a privileged service account on a spoke cluster to submit a malicious CSR. Successful exploitation can lead to privilege escalation, enabling the attacker to obtain administrative credentials on the hub cluster.
Vulnerability class: Improper Certificate Validation
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.
Affected products
Weakness classification (CWE)
References
- secalert@redhat.com (x_refsource_REDHAT, vdb-entry)
- secalert@redhat.com (x_refsource_REDHAT, issue-tracking)
Frequently asked questions
- What is CVE-2026-66795?
- CVE-2026-66795 is a critical-severity vulnerability in Red Hat Multicluster Engine For Kubernetes, classified under Improper Certificate Validation. CVSS score: 9.1/10. Published 2026-08-17.
- How severe is CVE-2026-66795?
- Critical severity. CVSS v3 base score is 9.1 out of 10.