CVE-2026-66795Managedcluster-import-controller: csr auto-approver does not validate certificate subject or signername (spoke→hub cluster-admin)
- 9.9CriticalCVSS base score
- 0.49%Exploitation in 30 daysEPSS · top 57% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By redhat
- 21 days later
· 21 days later
Published
- 43 days later
· 43 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| redhatCNA (assigner) | 3.1 | Critical9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| NVDNVD · Awaiting Analysis | 3.1 | Critical9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.49% · top 57% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.9.
Affected products
Red Hat · multicluster engine for Kubernetes 2.10
- unaffected 1787078272 – < *
Red Hat · multicluster engine for Kubernetes 2.11
- unaffected 1787078330 – < *
Red Hat · multicluster engine for Kubernetes 2.17
- unaffected 1786577915 – < *
Red Hat · multicluster engine for Kubernetes 2.6
- unaffected 1787260779 – < *
Red Hat · multicluster engine for Kubernetes 2.8
- unaffected 1787259044 – < *
Red Hat · multicluster engine for Kubernetes 2.9
- unaffected 1787078307 – < *
What to do
Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
References
References8
- RHSA-2026:59556 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2026:59557 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2026:59558 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2026:59559 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2026:59579 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2026:59593 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-66795 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2507540 (opens in a new tab)issue-trackingx_refsource_REDHAT
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-60452 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-66795)Record last updated .