high7.7
CVE-2026-106509
Backstage: Improper validation of MkDocs theme configuration in TechDocs
Impact
Backstage is an open framework for building developer portals. Prior to 1.14.6, the @backstage/plugin-techdocs-node package is affected by 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. This issue is fixed in versions 1.14.6 and 1.15.4.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| npm | @backstage/plugin-techdocs-node | < 1.15.4 | 1.15.4 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Linuxfoundation | Backstage Plugin-Techdocs-Node | before 1.14.6 from 1.15.0 before 1.15.4 |
| Linuxfoundation | Backstage | before 1.50.5 from 1.51.1 before 1.54.6 Version 1.51.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-8w7q-29mw-gf5c
- 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/releases/tag/v1.50.5
- https://github.com/backstage/backstage/releases/tag/v1.54.6