Submariner is a Kubernetes operator that facilitates direct networking between pods and services across different Kubernetes clusters by implementing KEP-1645 (Multi-Cluster Services API). The Red Hat security advisory RHSA-2026:36873 announces security fixes and updated container images for Submariner v0.20, included in Red Hat Advanced Cluster Management for Kubernetes 2.13. The advisory addresses multiple vulnerabilities (including CVE-2025-47950) and resolves several downstream issues. The update is rated as having an Important security impact by Red Hat Product Security. No CVSS base score is provided for CVE-2025-47950. The advisory references upstream Submariner release notes and Red Hat documentation for detailed fixes and prerequisites.

The vulnerabilities addressed in this update affect the security of cross-cluster networking in Kubernetes environments using Submariner v0.20. Exploitation could potentially impact the confidentiality, integrity, or availability of inter-cluster communications. Red Hat rates the overall security impact as Important (high severity). There are no known exploits in the wild at the time of the advisory.

Red Hat has released updated container images and security fixes for Submariner v0.20 as part of Red Hat Advanced Cluster Management for Kubernetes 2.13. Users should apply these updates to remediate the vulnerabilities. Detailed release notes and prerequisites are available in the upstream Submariner release notes and Red Hat documentation. There is no indication that no action is required; therefore, timely update is recommended. Patch status is confirmed by the vendor advisory.