Description
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.
References8
- access.redhat.com/errata/RHSA-2026:59556
- access.redhat.com/errata/RHSA-2026:59557
- access.redhat.com/errata/RHSA-2026:59558
- access.redhat.com/errata/RHSA-2026:59559
- access.redhat.com/errata/RHSA-2026:59579
- access.redhat.com/errata/RHSA-2026:59593
- access.redhat.com/security/cve/CVE-2026-66795
- bugzilla.redhat.com/show_bug.cgi?id=2507540
Metrics
- CVSS 3.1
-
9.9
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 43 · as of 11 November 2026
- CWE
- CWE-295
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.