1. Ubuntu Security Notices
  2. USN-5690-1

USN-5690-1: libXdmcp vulnerability

Publication date

19 October 2022

Overview

libXdmcp could be made to expose sensitive information.

Releases

Packages

  • libxdmcp - X11 authorisation library (development headers)

Details

It was discovered that libXdmcp was generating weak session keys.
A local attacker could possibly use this issue to perform a brute
force attack and obtain another user’s key.

It was discovered that libXdmcp was generating weak session keys.
A local attacker could possibly use this issue to perform a brute
force attack and obtain another user’s key.

Update instructions

In general, a standard system update will 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
16.04 xenial libxdmcp6 –  1:1.1.2-1.1ubuntu0.1~esm1  
14.04 trusty libxdmcp6 –  1:1.1.1-1ubuntu0.1~esm1  

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References

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