CVE-2026-106561: Backstage has a sensitive information disclosure in Kubernetes resource queries

An authenticated user holding the standard Kubernetes resource read permission could retrieve sensitive values that the Kubernetes plugin is designed to mask, potentially exposing credentials and other confidential material held in the connected clusters. Exposure is limited to resources that the Backstage service account is permitted to read and that match the targeted catalog entity’s namespace and label selector. Deployments whose cluster credentials do not grant read access to these resources are unaffected.