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.
https://gitlab.gnome.org/GNOME/gdm/commit/ff98b28
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-12164
Source: Mitre, NVD
Published: 2018-07-26
Updated: 2019-10-09
Base Score: 6.9
Vector: CVSS2#AV:L/AC:M/Au:N/C:C/I:C/A:C
Severity: Medium
Base Score: 6.4
Vector: CVSS:3.0/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H