CVE-2026-97026 Flatpak: flatpak: world-writable temporary child repositories in system-helper cache path
Local attackers can cause denial of service by tampering with world-writable temporary Flatpak directories on multi-user systems with permissive umask settings.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-97026?
CVE-2026-97026 is a low-severity vulnerability in Red Hat Enterprise Linux 10, published on 28 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
Flatpak creates temporary child repository directories under the user cache with world-writable permissions (0777). On multi-user systems with a permissive umask, other local users could read or modify the temporary directory used while installing apps or runtimes, potentially causing installation failures (denial of service); tampered content would fail signature/digest verification rather than being trusted.
Weakness: CWE-378
Which versions are affected by CVE-2026-97026?
How do I fix CVE-2026-97026?
Apply the vendor's patch.
Is CVE-2026-97026 being exploited?
There is no known exploitation of CVE-2026-97026 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-97026, UBUNTU-CVE-2026-97026.