Ubuntu 23.04 USN-6168-1 Critical: libx11 Denial of Service

ubuntu

June 15, 2023

libx11 could be made to crash if it received specially crafted network traffic.

Summary

libx11 could be made to crash if it received specially crafted network

traffic.

Software Description:

- libx11: X11 client-side library

Details:

Gregory James Duck discovered that libx11 incorrectly handled certain

Request, Event, or Error IDs. If a user were tricked into connecting to a

malicious X Server, a remote attacker could possibly use this issue to

cause libx11 to crash, resulting in a denial of service.

Topics Covered

security advisory denial of service Ubuntu network exploit libx11

Update Instructions

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 23.04:
   libx11-6                        2:1.8.4-2ubuntu0.2

Ubuntu 22.10:
   libx11-6                        2:1.8.1-2ubuntu0.2

Ubuntu 22.04 LTS:
   libx11-6                        2:1.7.5-1ubuntu0.2

Ubuntu 20.04 LTS:
   libx11-6                        2:1.6.9-2ubuntu1.5

After a standard system update you need to reboot your computer to make all
the necessary changes.