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.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 2
- StatusAwaiting Analysis → PublishedNVD modified 2026-10-24 03:08
- First seenCVSS 8.7NVD modified 2026-10-24 04:18
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 8
- https://access.redhat.com/security/cve/CVE-2026-94422
- https://bugzilla.redhat.com/show_bug.cgi?id=2542235
- https://github.com/flatpak/xdg-dbus-proxy/commit/e4465a0dfe96da3b39929a30a1ac3a22b16223e3
- https://github.com/flatpak/xdg-dbus-proxy/commit/e5702fca4dba9600721921fbca2dbc39dc5ca400
- https://github.com/flatpak/xdg-dbus-proxy/commit/fc027f759316fb2a6c45648200b6f100202eb84e
- https://github.com/flatpak/xdg-dbus-proxy/security/advisories/GHSA-2cgv-pwcq-wvpq
- http://www.openwall.com/lists/oss-security/2026/09/23/5
- https://lists.debian.org/debian-lts-announce/2026/10/msg00050.html