A Heimdal security update has been released for Ubuntu Linux 14.04 ESM, 16.04 ESM, 18.04 LTS, and 20.04 LTS.

USN-5766-1: Heimdal vulnerability

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Ubuntu Security Notice USN-5766-1
December 07, 2022

heimdal vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 ESM
- Ubuntu 14.04 ESM

Summary:

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

Software Description:
- heimdal: Heimdal Kerberos Network Authentication Protocol

Details:

It was discovered that Heimdal did not properly manage memory when
normalizing Unicode. An attacker could possibly use this issue to
cause a denial of service.

Update instructions:

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

Ubuntu 20.04 LTS:
libwind0-heimdal 7.7.0+dfsg-1ubuntu1.2

Ubuntu 18.04 LTS:
libwind0-heimdal 7.5.0+dfsg-1ubuntu0.2

Ubuntu 16.04 ESM:
libwind0-heimdal 1.7~git20150920+dfsg-4ubuntu1.16.04.1+esm2

Ubuntu 14.04 ESM:
libwind0-heimdal 1.6~git20131207+dfsg-1ubuntu1.2+esm2

After a standard system update you need to restart any application
using Heimdal libraries to make all the necessary changes.

References:
https://ubuntu.com/security/notices/USN-5766-1
CVE-2022-41916

Package Information:
https://launchpad.net/ubuntu/+source/heimdal/7.7.0+dfsg-1ubuntu1.2
https://launchpad.net/ubuntu/+source/heimdal/7.5.0+dfsg-1ubuntu0.2