CVE-2026-25152: backstage Path Traversal

Vulnerability summary

CVE-2026-25152 is a medium (CVSS 6.5) Path Traversal vulnerability in backstage. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 36.8% of scored vulnerabilities.

Timeline

1. 30-01-2026
   PublishedVulnerability first disclosed.
2. 02-02-2026
   Last modifiedVulnerability information updated.

Description

Backstage is an open framework for building developer portals, and @backstage/plugin-techdocs-node provides common node.js functionalities for TechDocs. In versions of @backstage/plugin-techdocs-node prior to 1.13.11 and 1.14.1, a path traversal vulnerability in the TechDocs local generator allows attackers to read arbitrary files from the host filesystem when Backstage is configured with `techdocs.generator.runIn: local`. When processing documentation from untrusted sources, symlinks within the docs directory are followed by MkDocs during the build process. File contents are embedded into generated HTML and exposed to users who can view the documentation. This vulnerability is fixed in` @backstage/plugin-techdocs-node` versions 1.13.11 and 1.14.1. Some workarounds are available. Switch to `runIn: docker` in `app-config.yaml` and/or restrict write access to TechDocs source repositories to trusted users only.

• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.