A X.Org X server security update has been released for Ubuntu Linux 14.04 ESM and 16.04 ESM.

USN-5778-2: X.Org X Server vulnerabilities

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Ubuntu Security Notice USN-5778-2
February 16, 2023

xorg-server, xorg-server-hwe-16.04 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 ESM
- Ubuntu 14.04 ESM

Summary:

Several security issues were fixed in X.Org X Server.

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

Details:

USN-5778-1 fixed several vulnerabilities in X.Org. This update provides
the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.

Original advisory details:

Jan-Niklas Sohn discovered that X.Org X Server extensions contained
multiple security issues. An attacker could possibly use these issues to
cause the X Server to crash, execute arbitrary code, or escalate
privileges.

Update instructions:

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

Ubuntu 16.04 ESM:
xserver-xorg-core 2:1.18.4-0ubuntu0.12+esm5
xserver-xorg-core-hwe-16.04 2:1.19.6-1ubuntu4.1~16.04.6+esm4
xwayland 2:1.18.4-0ubuntu0.12+esm5
xwayland-hwe-16.04 2:1.19.6-1ubuntu4.1~16.04.6+esm4

Ubuntu 14.04 ESM:
xserver-xorg-core 2:1.15.1-0ubuntu2.11+esm7

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

References:
  https://ubuntu.com/security/notices/USN-5778-2
  https://ubuntu.com/security/notices/USN-5778-1
CVE-2022-4283, CVE-2022-46340, CVE-2022-46341, CVE-2022-46342,
CVE-2022-46343, CVE-2022-46344, CVE-2023-0494