1. Ubuntu Security Notices
  2. USN-6555-2

USN-6555-2: X.Org X Server vulnerabilities

Publication date

13 December 2023

Overview

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

Releases

Packages

Details

USN-6555-1 fixed several vulnerabilities in X.Org. This update provides
the corresponding update for Ubuntu 16.04 LTS and Ubuntu 18.04 LTS.

Original advisory details:

Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled XKB
button actions. An attacker could possibly use this issue to cause the X
Server to crash, execute arbitrary code, or escalate privileges.
(CVE-2023-6377)

Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled
memory when processing the RRChangeOutputProperty and
RRChangeProviderProperty APIs. An attacker could possibly use this issue to
cause the X Server to crash, or obtain sensitive information.
(CVE-2023-6478)

USN-6555-1 fixed several vulnerabilities in X.Org. This update provides
the corresponding update for Ubuntu 16.04 LTS and Ubuntu 18.04 LTS.

Original advisory details:

Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled XKB
button actions. An attacker could possibly use this issue to cause the X
Server to crash, execute arbitrary code, or escalate privileges.
(CVE-2023-6377)

Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled
memory when processing the RRChangeOutputProperty and
RRChangeProviderProperty APIs. An attacker could possibly use this issue to
cause the X Server to crash, or obtain sensitive information.
(CVE-2023-6478)

Update instructions

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

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
18.04 bionic xserver-xorg-core –  2:1.19.6-1ubuntu4.15+esm3  
xwayland –  2:1.19.6-1ubuntu4.15+esm3  
16.04 xenial xserver-xorg-core –  2:1.18.4-0ubuntu0.12+esm8  
xwayland –  2:1.18.4-0ubuntu0.12+esm8  

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References

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