CVE-2026-94422
HighCVSS 8.8Summary
xdg-dbus-proxy before version 0.1.9 has an incorrect implementation of message filtering that allows an attacker to bypass intended 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.
Risk Assessment
The organization may be exposed to sandbox escape of Flatpak applications, potentially leading to unauthorized access to the system or data if applications are run in a Flatpak environment.
Recommendation
It is recommended to upgrade xdg-dbus-proxy to version 0.1.9 or later and review sandbox configurations for Flatpak and Firejail.
Other vulnerabilities in xdg-dbus-proxy
See all- CVE-2026-93676Low
xdg-dbus-proxy incorrectly filters D-Bus broadcast messages, bypassing configured path, interface, and member restrictions. This allows a sandboxed Flatpak application to intercept broadcast signals on the D-Bus session bus and AT-SPI bus that should be restricted.
- CVE-2026-34080Medium
xdg-dbus-proxy before version 0.1.7 has a policy parser vulnerability that allows bypassing eavesdrop restrictions. The proxy mishandles cases like 'eavesdrop ='true'' (with a space before the equals sign), enabling clients to intercept D-Bus messages they should not have access to.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS