CVE-2026-4740

Severity CVSS v4.0:

Pending analysis

Type:

CWE-295 Improper Certificate Validation

Publication date:

07/04/2026

Last modified:

07/04/2026

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.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 8.20 HIGH
Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): High
User Interaction (UI): None
Scope (S): Changed
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x

8.20

Severity 3.x

HIGH

CVE-2026-4740

Description

Impact

References to Advisories, Solutions, and Tools