CVE-2026-66795: managedcluster-import-controller: managedcluster-import-controller: CSR auto-approver does not validate certificate Subject, signerName, or requester identity

Severity: Critical

CVSS Score: 9.1

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.