An Avahi security update has been released for Ubuntu Linux 20.04 LTS, 22.04 LTS, 22.10, and 23.04.

[USN-6129-1] Avahi vulnerability

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Ubuntu Security Notice USN-6129-1
June 01, 2023

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

- Ubuntu 23.04
- Ubuntu 22.10
- Ubuntu 22.04 LTS
- Ubuntu 20.04 LTS

Summary:

Avahi could be made to crash if it received specially crafted DBus traffic.

Software Description:
- avahi: IPv4LL network address configuration daemon

Details:

It was discovered that Avahi incorrectly handled certain DBus messages. A
local attacker could possibly use this issue to cause Avahi to crash,
resulting in a denial of service.

Update instructions:

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

Ubuntu 23.04:
avahi-daemon 0.8-6ubuntu1.23.04.1

Ubuntu 22.10:
avahi-daemon 0.8-6ubuntu1.22.10.1

Ubuntu 22.04 LTS:
avahi-daemon 0.8-5ubuntu5.1

Ubuntu 20.04 LTS:
avahi-daemon 0.7-4ubuntu7.2

In general, a standard system update will make all the necessary changes.

References:
https://ubuntu.com/security/notices/USN-6129-1
CVE-2023-1981

Package Information:
https://launchpad.net/ubuntu/+source/avahi/0.8-6ubuntu1.23.04.1
https://launchpad.net/ubuntu/+source/avahi/0.8-6ubuntu1.22.10.1
https://launchpad.net/ubuntu/+source/avahi/0.8-5ubuntu5.1
https://launchpad.net/ubuntu/+source/avahi/0.7-4ubuntu7.2