1. Ubuntu Security Notices
  2. USN-4976-2

USN-4976-2: Dnsmasq vulnerability

Publication date

7 September 2022

Overview

Dnsmasq could be exposed to cache poisoning.

Releases

Packages

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

Details

USN-4976-1 fixed a vulnerability in Dnsmasq. This update provides
the corresponding update for Ubuntu 16.04 ESM.

Dnsmasq has been updated to 2.79-1 for Ubuntu 16.04 ESM in order to fix
some security issues.

Original advisory details:

Petr Mensik discovered that Dnsmasq incorrectly randomized source ports in
certain configurations. A remote attacker could possibly use this issue to
facilitate DNS cache poisoning attacks.

USN-4976-1 fixed a vulnerability in Dnsmasq. This update provides
the corresponding update for Ubuntu 16.04 ESM.

Dnsmasq has been updated to 2.79-1 for Ubuntu 16.04 ESM in order to fix
some security issues.

Original advisory details:

Petr Mensik discovered that Dnsmasq incorrectly randomized source ports in
certain configurations. A remote attacker could possibly use this issue to
facilitate DNS cache poisoning attacks.

Update instructions

After a standard system update you need to reboot your computer to 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 dnsmasq –  2.79-1ubuntu0.16.04.1+esm1  
dnsmasq-utils –  2.79-1ubuntu0.16.04.1+esm1  
dnsmasq-base –  2.79-1ubuntu0.16.04.1+esm1  

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References

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