USN-6168-2: libx11 vulnerability

20 June 2023

libx11 could be made to crash if it received specially crafted network traffic.

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Releases

Packages

  • libx11 - X11 client-side library

Details

USN-6168-1 fixed a vulnerability in libx11. This update provides
the corresponding update for Ubuntu 14.04 ESM, Ubuntu 16.04 ESM,
and Ubuntu 18.04 ESM.

Original advisory details:

Gregory James Duck discovered that libx11 incorrectly handled certain
Request, Event, or Error IDs. If a user were tricked into connecting to a
malicious X Server, a remote attacker could possibly use this issue to
cause libx11 to crash, resulting in a denial of service.

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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
Ubuntu 14.04

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

References

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