flatpak-builder is a tool to build flatpaks from source. From 1.4.5 to before 1.4.8, the license-files manifest key takes an array of paths to user defined licence files relative to the source directory of the module. The paths from that array are resolved using g_file_resolve_relative_path() and validated to stay inside the source directory using two checks - g_file_get_relative_path() which does not resolve symlinks and g_file_query_file_type() with G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS which only applies to the final path component. The copy operation runs on host. This can be exploited by using a crafted manifest and/or source to read arbitrary files from the host and capture them into the build output. This vulnerability is fixed in 1.4.8.
Fix
Patch, vendor advisory and mitigation references on NVD 1
- https://github.com/flatpak/flatpak-builder/security/advisories/GHSA-6gm9-3g7m-3965 Exploit, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 7.1 · flatpakNVD modified 2026-10-26 00:10
Affected (CPE criteria) 1
cpe:2.3:a:flatpak:flatpak-builder:*:*:*:*:*:*:*:*
References 1
- https://github.com/flatpak/flatpak-builder/security/advisories/GHSA-6gm9-3g7m-3965 Exploit, Vendor Advisory