Weblate: Prefix-Based Repository Boundary Check Bypass via Symlink/Junction Path Prefix Collision

Impact

Weblate repository-boundary validation relies on string prefix checks on resolved absolute paths. In multiple code paths, the check uses startswith against the repository root path. This is not path-segment aware and can be bypassed when the external path shares the same string prefix as the repository path (for example, repo and repo_outside).

Patches

• https://github.com/WeblateOrg/weblate/pull/18847

References

Thanks to m9nx4u for reporting this issue via HackerOne.