| Name | CVE-2022-21682 |
| Description | Flatpak is a Linux application sandboxing and distribution framework. A path traversal vulnerability affects versions of Flatpak prior to 1.12.3 and 1.10.6. flatpak-builder applies `finish-args` last in the build. At this point the build directory will have the full access that is specified in the manifest, so running `flatpak build` against it will gain those permissions. Normally this will not be done, so this is not problem. However, if `--mirror-screenshots-url` is specified, then flatpak-builder will launch `flatpak build --nofilesystem=host appstream-utils mirror-screenshots` after finalization, which can lead to issues even with the `--nofilesystem=host` protection. In normal use, the only issue is that these empty directories can be created wherever the user has write permissions. However, a malicious application could replace the `appstream-util` binary and potentially do something more hostile. This has been resolved in Flatpak 1.12.3 and 1.10.6 by changing the behaviour of `--nofilesystem=home` and `--nofilesystem=host`. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DSA-5049-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| flatpak (PTS) | stretch | 0.8.9-0+deb9u3 | vulnerable |
| stretch (security), stretch (lts) | 0.8.9-0+deb9u2 | vulnerable | |
| buster (security), buster, buster (lts) | 1.2.5-0+deb10u4 | vulnerable | |
| bullseye (security), bullseye | 1.10.8-0+deb11u2 | fixed | |
| bookworm (security), bookworm | 1.14.10-1~deb12u1 | fixed | |
| sid, trixie | 1.14.10-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| flatpak | source | bullseye | 1.10.7-0+deb11u1 | DSA-5049-1 | ||
| flatpak | source | (unstable) | 1.12.3-1 |
[buster] - flatpak <ignored> (Intrusive and risky to backport)
[stretch] - flatpak <ignored> (Intrusive and risky to backport)
https://github.com/flatpak/flatpak/security/advisories/GHSA-8ch7-5j3h-g4fx
https://github.com/flatpak/flatpak/commit/445bddeee657fdc8d2a0a1f0de12975400d4fc1a
Documentation: https://github.com/flatpak/flatpak/commit/4d11f77aa7fd3e64cfa80af89d92567ab9e8e6fa
1.12.4 added further changes to avoid regressions for some workflows