CVE-2026-106509: Backstage: Improper validation of MkDocs theme configuration in TechDocs
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.
References
- github.com/advisories/GHSA-8w7q-29mw-gf5c
- github.com/backstage/backstage/commit/02cd7cdbb18b687446277b5602adaee7f1d53cbb
- github.com/backstage/backstage/commit/a900a9953c8f7ad3ba1906d1d257725a9996cc9d
- github.com/backstage/backstage/releases/tag/v1.50.5
- github.com/backstage/backstage/releases/tag/v1.54.6
- github.com/backstage/backstage/security/advisories/GHSA-8w7q-29mw-gf5c
- nvd.nist.gov/vuln/detail/CVE-2026-106509
Code Behaviors & Features
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