CVE-2019-3825

A vulnerability was discovered in gdm before 3.31.4. When timed login is enabled in configuration, an attacker could bypass the lock screen by selecting the timed login user and waiting for the timer to expire, at which time they would gain access to the logged-in user's session.

CVE-2016-1000002

gdm3 3.14.2 and possibly later has an information leak before screen lock