CVE-2026-66783: Submariner-operator: release workflow consumes same-org composite action via mutable @devel branch ref

Severity: medium (CVSS 4.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-18 · updated 2026-10-19
Weakness: CWE-1357

Description

A flaw was found in the `submariner-operator` component of Red Hat Advanced Cluster Management for Kubernetes. This vulnerability allows a cluster administrator, or any user with permissions to modify the Submariner Custom Resource (CR), to specify an unvalidated image path. This lack of validation enables an attacker to execute arbitrary code with elevated privileges across the entire cluster, including control-plane nodes, by deploying a malicious image.

Affected products

Red Hat Advanced Cluster Management for Kubernetes 2: all versions
Red Hat Advanced Cluster Management for Kubernetes 2.16: all versions — fixed in 1790670243, 1790670912
Red Hat Advanced Cluster Management for Kubernetes 2.17: all versions — fixed in 1788073481, 1788105072

How to fix

Upgrade to a fixed version: Red Hat Advanced Cluster Management for Kubernetes 2.16 1790670243, 1790670912; Red Hat Advanced Cluster Management for Kubernetes 2.17 1788073481, 1788105072. Check the vendor advisory for mitigations.

References

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