GNOME Display Manager (GDM)

The daemon in GDM through 3.29.1 does not properly unexport display objects from its D-Bus interface when they are destroyed, which allows a local attacker to trigger a use-after-free via a specially crafted sequence of D-Bus method calls, resulting in a denial of service or potential code execution.

gdm3 would start gnome-initial-setup if it cannot contact accountservice

GNOME Display Manager (gdm) before 3.18.2 allows physically proximate attackers to bypass the lock screen by holding the Escape key.

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.

A flaw was discovered in gdm 3.24.1 where gdm greeter was no longer setting the ran_once boolean during autologin. If autologin was enabled for a victim, an attacker could simply select 'login as another user' to unlock their screen.

GNOME Display Manager (gdm) before 2.21.1 allows local users to change permissions of arbitrary directories via a symlink attack on /tmp/.X11-unix/.

A flaw was found in GDM in versions prior to 3.38.2.1. A race condition in the handling of session shutdown makes it possible to bypass the lock screen for a user that has autologin enabled, accessing their session without authentication. This is similar to CVE-2017-12164, but requires more difficult conditions to exploit.

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

GNOME Display Manager (gdm) 3.4.1 and earlier, when disable-user-list is set to true, allows local users to cause a denial of service (unable to login) by pressing the cancel button after entering a user name.

vicious-extensions/ve-misc.c in GNOME Display Manager (gdm) 2.20.x before 2.20.11, when GDM debug is enabled, logs the user password when it contains invalid UTF8 encoded characters, which might allow local users to gain privileges by reading the information from syslog logs.