CVE-2022-21682
Vulnérabilité élevée dans flatpak (flatpak)
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`.
Gravité et risque d'exploitation
CVE-2022-21682 obtient un score CVSS de 7.7/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 1.68 %, ce qui la place devant 76.6 % des CVE référencées.
Que faire ?
- Vérifiez si flatpak (versions < 1.10.6, >= 1.11.0, < 1.12.3) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.
Références
- https://github.com/flatpak/flatpak/security/advisories/GHSA-8ch7-5j3h-g4fx
- https://github.com/flatpak/flatpak/commit/445bddeee657fdc8d2a0a1f0de12975400d4fc1a
- https://github.com/flatpak/flatpak/commit/4d11f77aa7fd3e64cfa80af89d92567ab9e8e6fa
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/APFTBYGJJVJPFVHRXUW5PII5XOAFI4KH/
- https://www.debian.org/security/2022/dsa-5049
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IXKBERLJRYV7KXKGXOLI6IOXVBQNN4DP/
- https://security.gentoo.org/glsa/202312-12
