USN-4488-1: X.Org X Server vulnerabilities

Releases

• Ubuntu 20.04 LTS
• Ubuntu 18.04 ESM
• Ubuntu 16.04 ESM

Packages

• xorg-server - X.Org X11 server
• xorg-server-hwe-16.04 - X.Org X11 server
• xorg-server-hwe-18.04 - X.Org X11 server

Details

Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled the
input extension protocol. A local attacker could possibly use this issue to
escalate privileges. (CVE-2020-14346)

Jan-Niklas Sohn discovered that the X.Org X Server incorrectly initialized
memory. A local attacker could possibly use this issue to obtain sensitive
information. (CVE-2020-14347)

Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled the
XkbSelectEvents function. A local attacker could possibly use this issue to
escalate privileges. (CVE-2020-14361)

Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled the
XRecordRegisterClients function. A local attacker could possibly use this
issue to escalate privileges. (CVE-2020-14362)

Update instructions

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

Ubuntu 20.04

• xserver-xorg-core - 2:1.20.8-2ubuntu2.3

Ubuntu 18.04

• xserver-xorg-core - 2:1.19.6-1ubuntu4.5
• xserver-xorg-core-hwe-18.04 - 2:1.20.8-2ubuntu2.2~18.04.2

Ubuntu 16.04

• xserver-xorg-core - 2:1.18.4-0ubuntu0.9
• xserver-xorg-core-hwe-16.04 - 2:1.19.6-1ubuntu4.1~16.04.3

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

References

• CVE-2020-14346
• CVE-2020-14347
• CVE-2020-14361
• CVE-2020-14362

Related notices

• USN-4488-2: xserver-xorg-dev, xnest, xdmx, xserver-common, xserver-xorg-core, xdmx-tools, xserver-xorg-xmir, xvfb, xorg-server-source, xorg-server, xserver-xephyr, xserver-xorg-core-udeb