CVE-2026-39977

Name
CVE-2026-39977
Description
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.
NVD Severity
unknown
Other trackers
Mailing lists
Exploits
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
security-advisories@github.com https://github.com/flatpak/flatpak-builder/security/advisories/GHSA-6gm9-3g7m-3965

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:flatpak:flatpak-builder:*:*:*:*:*:*:*:* flatpak-builder >= 1.4.5 < 1.4.8

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
flatpak-builder edge-community 1.4.7-r1 André Klitzing <aklitzing@gmail.com> possibly vulnerable
flatpak-builder edge-community 1.4.7-r0 André Klitzing <aklitzing@gmail.com> possibly vulnerable
flatpak-builder edge-community 1.4.6-r0 André Klitzing <aklitzing@gmail.com> possibly vulnerable
flatpak-builder 3.23-community 1.4.7-r0 André Klitzing <aklitzing@gmail.com> possibly vulnerable