FKIE_CVE-2026-4740

Vulnerability from fkie_nvd - Published: 2026-04-07 15:17 - Updated: 2026-06-17 10:57
Severity
8.2 (High) - CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Summary
A flaw was found in Open Cluster Management (OCM), the technology underlying Red Hat Advanced Cluster Management (ACM). Improper validation of Kubernetes client certificate renewal allows a managed cluster administrator to forge a client certificate that can be approved by the OCM controller. This enables cross-cluster privilege escalation and may allow an attacker to gain control over other managed clusters, including the hub cluster.
References
secalert@redhat.comhttps://access.redhat.com/security/cve/CVE-2026-4740Vendor Advisory
secalert@redhat.comhttps://blog.arfevrier.fr/open-cluster-management-cross-cluster-escape/Exploit, Third Party Advisory
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2450590Issue Tracking, Vendor Advisory
Impacted products
Vendor Product Version
redhat advanced_cluster_management_for_kubernetes -
To clipboard 

{
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    }
  ],
  "id": "CVE-2026-4740",
  "lastModified": "2026-06-17T10:57:09.237",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
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          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "HIGH",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
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            {
              "technicalImpact": "total"
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          "role": "CISA Coordinator",
          "timestamp": "2026-04-09T14:40:37.454585Z",
          "version": "2.0.3"
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}


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