Threats affecting pkg:github/flatpak/xdg-desktop-portal

A path traversal vulnerability (CWE-22) exists in flatpak's xdg-desktop-portal prior to version 1.22.1. Malicious sandboxed applications can exploit the FileChooser.SaveFiles method to gain arbitrary file access to non-existing files on the host system, limited to files accessible by the user. The vulnerability arises because filenames passed to the method are not properly validated by the frontend or common backends, allowing path traversal. This issue has been patched in version 1.22.1.

XDG Desktop Portal is a desktop integration portal. Prior to version 1.22.1, malicious sandboxed applications can use the FileTransfer.RetrieveFiles method to redirect drag-and-drop and copy-paste data targeted at other applications to itself. Some portals generate tokens which provide access to resources. The sharing of the token transfers access to the resource and is supposed to happen out of band. The tokens were generated with g_random_int or g_uuid_string_random, both of which use GLib's GRand based on the Mersenne Twister PRNG which created a stream of reproducible random numbers. By generating enough tokens, the state of the GRand can be recover and with it, the next tokens can be predictedinsufin. This issue has been patched in version 1.22.1.

Flatpak xdg-desktop-portal before 1.20.4 and 1.21.x before 1.21.1 allows any Flatpak app to trash any file in the host context via a symlink attack on g_file_trash.