CVE-2026-25704: Pop-OS Cosmic-Greeter

Medium severity, CVSS 5.8. EPSS: 0.1% chance of exploitation in the next 30 days.

A Privilege Dropping / Lowering Errors/Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in  cosmic-greeter can allow an attacker to regain privileges that should have been dropped and abuse them in the racy checking logic. This issue affects cosmic-greeter before https://github.Com/pop-os/cosmic-greeter/pull/426.

Affected products

• Pop-OS Cosmic-Greeter

Published 2026-03-30. Last modified 2026-06-17.