USN-6034-1: Dnsmasq vulnerability

Releases

• Ubuntu 22.10
• Ubuntu 22.04 LTS
• Ubuntu 20.04 LTS
• Ubuntu 18.04 ESM
• Ubuntu 16.04 ESM
• Ubuntu 14.04 ESM

Packages

• dnsmasq - Small caching DNS proxy and DHCP/TFTP server

Details

It was discovered that Dnsmasq was sending large DNS messages
over UDP, possibly causing transmission failures due to IP
fragmentation. This update lowers the default maximum size of
DNS messages to improve transmission reliability over UDP.

Update instructions

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

Ubuntu 22.10

• dnsmasq-base - 2.86-1.1ubuntu2.1

Ubuntu 22.04

• dnsmasq-base - 2.86-1.1ubuntu0.3

Ubuntu 20.04

• dnsmasq-base - 2.80-1.1ubuntu1.7

Ubuntu 18.04

• dnsmasq-base - 2.79-1ubuntu0.7

Ubuntu 16.04

• dnsmasq-base - 2.79-1ubuntu0.16.04.1+esm2
  Available with Ubuntu Pro

Ubuntu 14.04

• dnsmasq-base - 2.68-1ubuntu0.2+esm2
  Available with Ubuntu Pro

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

References

• CVE-2023-28450

Related notices

• USN-6657-1: dnsmasq-utils, dnsmasq, dnsmasq-base-lua, dnsmasq-base
• USN-6657-2: dnsmasq-utils, dnsmasq, dnsmasq-base-lua, dnsmasq-base