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

13 December 2023

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

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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)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 18.04
Ubuntu 16.04

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

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