CVE-2026-4740

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"https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}, {"cpes": ["cpe:/a:redhat:multicluster_engine"], "vendor": "Red Hat", "product": "Multicluster Engine for Kubernetes", "packageName": "multicluster-engine/placement-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}, {"cpes": ["cpe:/a:redhat:multicluster_engine"], "vendor": "Red Hat", "product": "Multicluster Engine for Kubernetes", "packageName": "multicluster-engine/registration-operator-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}, {"cpes": ["cpe:/a:redhat:multicluster_engine"], "vendor": "Red Hat", "product": "Multicluster Engine for Kubernetes", "packageName": "multicluster-engine/work-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}]}], "published": "2026-04-07T15:17:46.797", "references": [{"url": "https://access.redhat.com/errata/RHSA-2026:11414", "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:13542", "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:13853", "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8218", "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:9848", "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/security/cve/CVE-2026-4740", "tags": ["Vendor Advisory"], "source": "secalert@redhat.com"}, {"url": "https://blog.arfevrier.fr/open-cluster-management-cross-cluster-escape/", "tags": ["Exploit", "Third Party Advisory"], "source": "secalert@redhat.com"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2450590", "tags": ["Issue Tracking", "Vendor Advisory"], "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:11414", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:13542", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:13853", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8218", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:9848", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/security/cve/CVE-2026-4740", "tags": ["Vendor Advisory"], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2450590", "tags": ["Issue Tracking", "Vendor Advisory"], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4740.json", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "secalert@redhat.com", "description": [{"lang": "en", "value": "CWE-295"}]}, {"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "description": [{"lang": "en", "value": "CWE-295"}]}], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "Se encontr\u00f3 una vulnerabilidad en Open Cluster Management (OCM), la tecnolog\u00eda subyacente a Red Hat Advanced Cluster Management (ACM). Una validaci\u00f3n incorrecta de la renovaci\u00f3n de certificados de cliente de Kubernetes permite a un administrador de cl\u00faster gestionado forjar un certificado de cliente que puede ser aprobado por el controlador de OCM. Esto permite la escalada de privilegios entre cl\u00fasteres y puede permitir a un atacante obtener control sobre otros cl\u00fasteres gestionados, incluyendo el cl\u00faster central."}], "lastModified": "2026-10-26T21:10:00.170", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:redhat:advanced_cluster_management_for_kubernetes:-:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7301AD20-0188-463F-9386-9D878AD3A542"}], "operator": "OR"}]}], "sourceIdentifier": "secalert@redhat.com"}