CVE-2026-94422 — xdg-dbus-proxy: message filtering bypass via reply serial allows sandbox escape
An incorrect implementation of message filtering in xdg-dbus-proxy versions before 0.1.9 allows an attacker to bypass the intended message filtering on the D-Bus session bus by …
Published: 2026-10-02 · CVSS: 8.7 · CVSS 4.0
An incorrect implementation of message filtering in xdg-dbus-proxy versions before 0.1.9 allows an attacker to bypass the intended message filtering on the D-Bus session bus by setting a reply serial number on non-reply messages. A malicious or compromised Flatpak app could use this to achieve arbitrary code execution outside its sandbox. xdg-dbus-proxy was designed to be part of the sandbox boundary for Flatpak, but it is released as a separate project and is sometimes used by other app frameworks such as Firejail.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7