CVE-2021-21381
flatpak - security update
描述
Flatpak is a system for building, distributing, and running sandboxed desktop applications on Linux. In Flatpack since version 0.9.4 and before version 1.10.2 has a vulnerability in the "file forwarding" feature which can be used by an attacker to gain access to files that would not ordinarily be allowed by the app's permissions. By putting the special tokens `@@` and/or `@@u` in the Exec field of a Flatpak app's .desktop file, a malicious app publisher can trick flatpak into behaving as though the user had chosen to open a target file with their Flatpak app, which automatically makes that file available to the Flatpak app. This is fixed in version 1.10.2. A minimal solution is the first commit "`Disallow @@ and @@U usage in desktop files`". The follow-up commits "`dir: Reserve the whole @@ prefix`" and "`dir: Refuse to export .desktop files with suspicious uses of @@ tokens`" are recommended, but not strictly required. As a workaround, avoid installing Flatpak apps from untrusted sources, or check the contents of the exported `.desktop` files in `exports/share/applications/*.desktop` (typically `~/.local/share/flatpak/exports/share/applications/*.desktop` and `/var/lib/flatpak/exports/share/applications/*.desktop`) to make sure that literal filenames do not follow `@@` or `@@u`.
如何修補 CVE-2021-21381
要修補 CVE-2021-21381,請將受影響套件升級到下列已修補版本。
- —升級至 1.10.1-4 或更新版本
- —升級至 1.2.5-0+deb10u4 或更新版本
CVE-2021-21381 正在被利用嗎?
低 — EPSS 為 1.5%,目前沒有觀察到大規模利用活動。
受影響套件(2)
- from 0, < 1.10.1-4
- from 0, < 1.2.5-0+deb10u4