CVE-2026-90616 (GCVE-0-2026-90616)
Vulnerability from cvelistv5
Published
2026-09-12 20:00
Modified
2026-09-14 18:22
CWE
  • CWE-61 - UNIX Symbolic Link (Symlink) Following
Summary
In Flatpak before 1.18.1, a malicious sandboxed app can obtain arbitrary read and write access to files on the host, which can be escalated to arbitrary code execution on the host, a different vulnerability than CVE-2026-76925. Flatpak creates a few app data directories (e.g., /var/cache, /var/data, /var/config, and /var/tmp) in every sandbox on every app launch where, in some cases, components of the path are attacker-controlled. Missing symlink protection can redirect the directories. Some of these directories are bind-mounted by Flatpak by passing the path (e.g., /home/user/.var/app/APP_ID/cache/tmp), which contains attacker-controlled directories (tmp) to bwrap --bind SRC DST. bwrap passes the path on to the kernel, which then follows symlinks. A malicious symlink can point to arbitrary locations on the host and it will become mounted inside the sandbox.
Impacted products
Vendor Product Version
Flatpak Flatpak Version: 0   ≤
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Show details on NVD website


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