CVE-2026-106501 [CRITICAL] – Backstage is an open framework for building developer portals. Prior to 3.3.1, 3.4.1, 4.0.

Backstage is an open framework for building developer portals. Prior to 3.3.1, 3.4.1, 4.0.3 and 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by sensitive information exposure in scaffolder. An authenticated Backstage user who can read another user’s Scaffolder task may receive internal execution data. In deployments where that data contains credentials for an external service, this may permit disclosure and unauthorized changes in that external service. This issue is fixed in versions 3.3.1, 3.4.1, 4.0.3 and 4.1.0.