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CVE-2026-4740

Redhat Advanced Cluster Management For Kubernetes privilege escalation

8.2 HIGHPublic exploitEPSS 0.16%
  1. Published7 Apr 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.

CVSS 3.1 breakdown

Attack vectorLocal
Attack complexityLow
Privileges requiredHigh
User interactionNone
ScopeChanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Affected products

Redhat Advanced Cluster Management For Kubernetesall versions

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

References

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Frequently asked

Is CVE-2026-4740 being actively exploited?

CVE-2026-4740 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 0.16%.

How severe is CVE-2026-4740?

CVE-2026-4740 has a CVSS 3.1 base score of 8.2, rated high. EPSS estimates a 0.16% probability of exploitation.

Which products are affected by CVE-2026-4740?

Affected products include Redhat Advanced Cluster Management For Kubernetes.

How do I fix CVE-2026-4740?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-4740 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.