CVE-2026-29186: TechDocs Mkdocs Configuration Key Enables Arbitrary Code Execution
(updated )
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.
References
- backstage.io/docs/features/techdocs/architecture
- github.com/advisories/GHSA-928r-fm4v-mvrw
- github.com/backstage/backstage
- github.com/backstage/backstage/security/advisories/GHSA-928r-fm4v-mvrw
- nvd.nist.gov/vuln/detail/CVE-2026-29186
- www.mkdocs.org/about/release-notes/
- www.mkdocs.org/user-guide/configuration/
Code Behaviors & Features
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