ReviewCritical

CVE-2026-66795

Red Hat multicluster engine for Kubernetes 2.10, multicluster engine for Kubernetes 2.11, multicluster engine for Kubernetes 2.17

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: 9.1
EPSS: -
CISA KEV: Not listed
Published: 2026.08.18

PRIORITY ASSESSMENT

Review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability-

Technical severityCVSS 9.1

Vulnerability overview

Affected product and versions

Product: Red Hat multicluster engine for Kubernetes 2.10, multicluster engine for Kubernetes 2.11, multicluster engine for Kubernetes 2.17
Affected versions: See the vendor advisory and NVD configuration data
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Red Hat multicluster engine for Kubernetes 2.10, multicluster engine for Kubernetes 2.11, multicluster engine for Kubernetes 2.17 and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CWE: CWE-295