CVE-2026-39977 (GCVE-0-2026-39977)

Vulnerability from cvelistv5 – Published: 2026-04-09 19:05 – Updated: 2026-04-09 20:19
VLAI?
Title
flatpak-builder has a path traversal leading to arbitrary file read on host when installing licence files
Summary
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.
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
References
Impacted products
Vendor Product Version
flatpak flatpak-builder Affected: >= 1.4.5, < 1.4.8
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Show details on NVD website

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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