USN-4976-1: Dnsmasq vulnerability

2 June 2021

Dnsmasq could be exposed to cache poisoning.

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Releases

Packages

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

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.

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 21.04
Ubuntu 20.10
Ubuntu 20.04
Ubuntu 18.04

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

References

Related notices

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Further reading