Description
Flatpak passes through arbitrary vendor-extension keys unmodified when exporting an application's Desktop Entry (.desktop) and D-Bus Service (.service) files, instead of validating against an allowlist. A malicious Flatpak app can use this to cause denial of service (e.g. forced application restart loops) or to influence host D-Bus/systemd activation behavior beyond what the sandbox is intended to permit.
References3
Metrics
- CVSS 3.1
-
3.6
LOW
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:L - EPSS — exploit probability
- 0% percentile: 2 · as of 9 November 2026
- CWE
- CWE-20
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.