Rapid7

vulnerability

Ubuntu: (CVE-2020-27837): gdm3 vulnerability

Severity
4
CVSS
(AV:L/AC:M/Au:N/C:P/I:P/A:P)
Published
Dec 28, 2020
Added
Jun 26, 2025
Modified
Mar 27, 2026

Description

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.

Solution

no-fix-ubuntu-package
Title
Rapid7 Labs

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