xorg-server, xorg-server-hwe-16.04, xorg-server-hwe-18.04 vulnerability

A security issue affects these releases of Ubuntu and its
derivatives:

* Ubuntu 20.04 LTS
* Ubuntu 18.04 LTS
* Ubuntu 16.04 LTS

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.

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

To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.

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

References

* CVE-2020-14345

--- Mystic BBS v1.12 A46 (Linux/64)
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