FKIE_CVE-2026-4740

Vulnerability from fkie_nvd - Published: 2026-04-07 15:17 - Updated: 2026-04-28 20:39
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": "2026-04-28T20:39:15.040",
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          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
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          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
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