8.2highHigh

CVE-2026-4740

Redhat Advanced Cluster Management For Kubernetes

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.

Exploitation status

  • Published references include exploit or proof-of-concept material. There is no confirmation it is being used in real attacks.
  • A vendor advisory or patch reference has been published.

What the metrics mean

  • It is requires local access to the machine.
  • For an attacker who can reach it, no special conditions are needed to exploit it.
  • To exploit it, an administrative account is needed.
  • Beyond that, no action by a user is required.

Scoring

CVSS
8.2 (v3.1)
Vector
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Weakness
CWE-295
Assigned by
secalert@redhat.com

Dates

Published
2026-04-07
Last modified
2026-09-08
Sources
NVD

Affected products

  • Redhat Advanced Cluster Management For Kubernetesall versions

As listed in the NVD configuration data. Not a statement about your estate.

References