{"schemaVersion":3,"id":"CVE-2026-29186","aliases":["GHSA-928r-fm4v-mvrw"],"status":"published","duplicateOf":null,"title":null,"description":"Backstage is an open framework for building developer portals. Prior to version 1.14.3, this is a configuration bypass vulnerability that enables arbitrary code execution. The @backstage/plugin-techdocs-node package uses an allowlist to filter dangerous MkDocs configuration keys during the documentation build process. A gap in this allowlist allows attackers to craft an mkdocs.yml that causes arbitrary Python code execution, completely bypassing TechDocs' security controls. 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