Ubuntu 20.04 LTS: USN-4490-1 Moderate: X.Org Server Crash Risk

ubuntu

September 8, 2020

X.Org X Server could be made to crash or run programs if it received specially crafted input.

Summary

X.Org X Server could be made to crash or run programs if it received

specially crafted input.

Software Description:

- xorg-server: X.Org X11 server

- xorg-server-hwe-18.04: X.Org X11 server

- xorg-server-hwe-16.04: X.Org X11 server

Details:

Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled the

XkbSetNames function. A local attacker could possibly use this issue to

escalate privileges.

Topics Covered

security advisory privilege escalation ubuntu input handling xorg-server program crash

Update Instructions

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

Ubuntu 20.04 LTS:
  xserver-xorg-core               2:1.20.8-2ubuntu2.4

Ubuntu 18.04 LTS:
  xserver-xorg-core               2:1.19.6-1ubuntu4.6
  xserver-xorg-core-hwe-18.04     2:1.20.8-2ubuntu2.2~18.04.3

Ubuntu 16.04 LTS:
  xserver-xorg-core               2:1.18.4-0ubuntu0.10
  xserver-xorg-core-hwe-16.04     2:1.19.6-1ubuntu4.1~16.04.4

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