GHSA-8w7q-29mw-gf5c Backstage: Improper validation of MkDocs theme configuration in TechDocs

• npm @backstage/plugin-techdocs-node: < 1.15.4 → fixed in 1.15.4

Impact When TechDocs is configured to build documentation locally or in a container, a user with write access to a registered repository can include configuration values in `mkdocs.yml` that cause arbitrary code execution during the documentation build process. Patches Patched in `@backstage/plugin-techdocs-node` version `1.15.4` Workarounds • Configure TechDocs with `techdocs.generator.runIn: 'docker'` instead of `'local'` to provide container isolation, though this does not fully mitigate the risk. • Restrict write access to repositories registered in the Backstage catalog to trusted users.