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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-4740 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://access.redhat.com/security/cve/CVE-2026-4740 Red Hat, Inc.
https://blog.arfevrier.fr/open-cluster-management-cross-cluster-escape/ Red Hat, Inc.
https://bugzilla.redhat.com/show_bug.cgi?id=2450590 Red Hat, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-295 Improper Certificate Validation Red Hat, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-4740
NVD Published Date:
04/07/2026
NVD Last Modified:
04/07/2026
Source:
Red Hat, Inc.