Backstage up to 0.1.16 link following

Summaryinfo

A vulnerability has been found in Backstage up to 0.1.16 and classified as critical. Affected by this issue is some unknown functionality. The manipulation leads to link following. This vulnerability is listed as CVE-2026-24047. The attack may be initiated remotely. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Backstage up to 0.1.16. It has been rated as problematic. This issue affects an unknown part. The manipulation with an unknown input leads to a link following vulnerability. Using CWE to declare the problem leads to CWE-59. The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource. Impacted is confidentiality. The summary by CVE is:

Backstage is an open framework for building developer portals, and @backstage/cli-common provides config loading functionality used by the backend and command line interface of Backstage. Prior to version 0.1.17, the `resolveSafeChildPath` utility function in `@backstage/backend-plugin-api`, which is used to prevent path traversal attacks, failed to properly validate symlink chains and dangling symlinks. An attacker could bypass the path validation via symlink chains (creating `link1 → link2 → /outside` where intermediate symlinks eventually resolve outside the allowed directory) and dangling symlinks (creating symlinks pointing to non-existent paths outside the base directory, which would later be created during file operations). This function is used by Scaffolder actions and other backend components to ensure file operations stay within designated directories. This vulnerability is fixed in `@backstage/backend-plugin-api` version 0.1.17. Users should upgrade to this version or later. Some workarounds are available. Run Backstage in a containerized environment with limited filesystem access and/or restrict template creation to trusted users.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-24047 since 01/20/2026. The exploitation is known to be difficult. The attack may be initiated remotely. Neither technical details nor an exploit are publicly available.

Upgrading to version 0.1.17 eliminates this vulnerability. Applying the patch ae4dd5d1572a4f639e1a466fd982656b50f8e692 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• Backstage

Version

• 0.1.0
• 0.1.1
• 0.1.2
• 0.1.3
• 0.1.4
• 0.1.5
• 0.1.6
• 0.1.7
• 0.1.8
• 0.1.9
• 0.1.10
• 0.1.11
• 0.1.12
• 0.1.13
• 0.1.14
• 0.1.15
• 0.1.16

License

• open-source

Website

• Product: https://github.com/backstage/backstage/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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