A libx11 security update has been released for Ubuntu Linux 18.04 LTS, 20.04 LTS, 20.10, and 21.04.
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Ubuntu Security Notice USN-4966-1
May 25, 2021
libx11 vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 21.04
- Ubuntu 20.10
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
Summary:
libx11 could allow unintended access to services.
Software Description:
- libx11: X11 client-side library
Details:
It was discovered that libx11 incorrectly validated certain parameter
lengths. A remote attacker could possibly use this issue to trick libx11
into emitting extra X protocol requests.
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 21.04:
libx11-6 2:1.7.0-2ubuntu0.1
Ubuntu 20.10:
libx11-6 2:1.6.12-1ubuntu0.1
Ubuntu 20.04 LTS:
libx11-6 2:1.6.9-2ubuntu1.2
Ubuntu 18.04 LTS:
libx11-6 2:1.6.4-3ubuntu0.4
After a standard system update you need to reboot your computer to make
all the necessary changes.
References:
https://ubuntu.com/security/notices/USN-4966-1
CVE-2021-31535
Package Information:
https://launchpad.net/ubuntu/+source/libx11/2:1.7.0-2ubuntu0.1
https://launchpad.net/ubuntu/+source/libx11/2:1.6.12-1ubuntu0.1
https://launchpad.net/ubuntu/+source/libx11/2:1.6.9-2ubuntu1.2
https://launchpad.net/ubuntu/+source/libx11/2:1.6.4-3ubuntu0.4
