Backstage: Improper validation of MkDocs theme configuration in TechDocs
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.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| npm package | @backstage/plugin-techdocs-node | < 1.15.4 | 1.15.4 |
References
- https://github.com/backstage/backstage/security/advisories/GHSA-8w7q-29mw-gf5c
- https://nvd.nist.gov/vuln/detail/CVE-2026-106509
- https://github.com/backstage/backstage/commit/02cd7cdbb18b687446277b5602adaee7f1d53cbb
- https://github.com/backstage/backstage/commit/a900a9953c8f7ad3ba1906d1d257725a9996cc9d
- https://github.com/backstage/backstage
- https://github.com/backstage/backstage/releases/tag/v1.50.5
- https://github.com/backstage/backstage/releases/tag/v1.54.6
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:L- Weakness (CWE)
CWE-1336, CWE-94- Platform
- npm
- Package
@backstage/plugin-techdocs-node- Disclosed
- 07.10.2026
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-8w7q-29mw-gf5c - CC BY 4.0
Vulnerability history: @backstage/plugin-techdocs-node
All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 11
- First → latest
- 06.2022 10.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- High 8
- Medium 3
Disclosures per year
- 2022: 1
- 2023: 0
- 2024: 0
- 2025: 0
- 2026: 10
-
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