# CVE-2026-66795

## Summary

- **CVE ID:** CVE-2026-66795
- **Severity:** CRITICAL
- **CVSS Score:** 9.9 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H)
- **CWE:** CWE-295
- **Published:** Aug 17, 2026
- **Last Modified:** Sep 8, 2026

## 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.

## Affected Products

- Red Hat — multicluster engine for Kubernetes 2.9.0 (1787078307)
- Red Hat — multicluster engine for Kubernetes 2.11 (1787078330)
- Red Hat — multicluster engine for Kubernetes 2.17 (1786577915)
- Red Hat — multicluster engine for Kubernetes 2.10 (1787078272)
- Red Hat — multicluster engine for Kubernetes 2.6 (1787260779)
- Red Hat — multicluster engine for Kubernetes 2.8 (1787259044)
- Red Hat — multicluster engine for Kubernetes 2.9 (1787078307)
- Red Hat — multicluster engine for Kubernetes 2.1 (1787078272)

## References

- [CNA](https://access.redhat.com/security/cve/CVE-2026-66795)
- [CNA](https://bugzilla.redhat.com/show_bug.cgi?id=2507540)
- [CNA](https://access.redhat.com/errata/RHSA-2026:59556)
- [CNA](https://access.redhat.com/errata/RHSA-2026:59593)
- [CNA](https://access.redhat.com/errata/RHSA-2026:59557)
- [CNA](https://access.redhat.com/errata/RHSA-2026:59558)
- [CNA](https://access.redhat.com/errata/RHSA-2026:59559)
- [CNA](https://access.redhat.com/errata/RHSA-2026:59579)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.32%
- **EPSS Percentile:** 24.8

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-18._