CVE-2026-97027

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.

Red Hat estimates the CVSSv3.1 vector of CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:L.

Exploitation requires a victim to install and run a malicious Flatpak application (UI:R), after which the unsanitized exported Desktop Entry / D-Bus Service keys take effect automatically with no additional attacker privileges or access complexity (AV:L, AC:L, PR:N). Because the exported files can influence D-Bus/systemd activation behavior on the host session outside the flatpak sandbox, this is treated as a scope change (S:C). No confidentiality or integrity impact is implied by the primary reported effect (C:N, I:N); the impact is limited to availability, via forced application restart loops or disrupted service activation (A:L).

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Only install applications from trusted sources.