A malicious or compromised Flatpak repository can write attacker-controlled content to arbitrary locations on the host filesystem via extract_extra_data(). On system installs, the write happens as root. Two issues combine: `files/extra` is resolved via path operations that follow symlinks, and blob names from `xa.extra-data-sources` are not sanitized against `..` traversal.
CVE-2026-96275
CVSS base score
8.8 (v3.1)
Severity
HIGH
Attack vector
Network
Weakness
CWE-22
Last modified
October 29, 2026
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H