Managedcluster-import-controller: csr auto-approver does not validate certificate subject or signername (spoke→hub cluster-admin)
28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.9epss 0.3%
exploitation probability
0.3%top 75% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Affected products
Red Hat · multicluster engine for Kubernetes 2.1Red Hat · multicluster engine for Kubernetes 2.11Red Hat · multicluster engine for Kubernetes 2.17Red Hat · multicluster engine for Kubernetes 2.6Red Hat · multicluster engine for Kubernetes 2.8Red Hat · multicluster engine for Kubernetes 2.9References
https://access.redhat.com/errata/RHSA-2026:59556https://access.redhat.com/errata/RHSA-2026:59557https://access.redhat.com/errata/RHSA-2026:59558https://access.redhat.com/errata/RHSA-2026:59559https://access.redhat.com/errata/RHSA-2026:59579https://access.redhat.com/errata/RHSA-2026:59593https://access.redhat.com/security/cve/CVE-2026-66795https://bugzilla.redhat.com/show_bug.cgi?id=2507540