Is CVE-2026-54099 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-54099 being exploited in the wild.

How severe is CVE-2026-54099?

High severity, with a CVSS score of 8.8, published 22 June 2026.

Which products and versions are affected?

Red Hat OpenShift for Windows Containers All; Red Hat Windows Machine Config Operator All versions prior to fix.

Is there a fix for CVE-2026-54099?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-54099 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-54099?

Check whether you run Red Hat OpenShift for Windows Containers or Red Hat Windows Machine Config Operator at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-54099: Red Hat WMCO privilege escalation in WICD CSR auto-approver

CVE-2026-54099 · Severity: high · CVSS 8.8 · Published 2026-06-22

A security flaw in the Red Hat OpenShift Windows Machine Config Operator (WMCO) allows an attacker who has already compromised a Windows worker node to escalate their privileges to full cluster administrator. The WMCO component, which manages Windows nodes within an OpenShift cluster, fails to properly verify certificate requests, allowing a restricted user to claim unauthorized administrative rights. This could lead to a total takeover of the entire container platform and all data hosted within it.

Vendors: Red Hat.

Quick answers

Is CVE-2026-54099 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-54099 being exploited in the wild.
How severe is CVE-2026-54099?: High severity, with a CVSS score of 8.8, published 22 June 2026.
Which products and versions are affected?: Red Hat OpenShift for Windows Containers All; Red Hat Windows Machine Config Operator All versions prior to fix.
Is there a fix for CVE-2026-54099?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-54099 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-54099?: Check whether you run Red Hat OpenShift for Windows Containers or Red Hat Windows Machine Config Operator at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A flaw exists in the Windows Instance Config Daemon (WICD) CSR auto-approver within the Windows Machine Config Operator (WMCO). The `ValidateCSR()` function verifies that a Certificate Signing Request (CSR) contains the 'system:wicd-nodes' organization but fails to reject or strip additional organization values. An attacker with local access to a Windows worker node and WICD credentials can submit a crafted CSR containing both 'system:wicd-nodes' and 'system:masters'. Because the 'kubernetes.io/kube-apiserver-client' signer does not filter these values, the resulting signed certificate grants the attacker 'system:masters' (cluster-admin) privileges, leading to a full cluster takeover.

Affected products

Red Hat OpenShift Container Platform 4 4
Red Hat OpenShift for Windows Containers All
Red Hat Windows Machine Config Operator (WMCO) All versions prior to fix

Timeline

2026-06-11: disclosed: Initial report in Red Hat Bugzilla
2026-06-22: advisory: CVE published by Red Hat and NVD

References

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