CVE-2021-3448

Published: 08 April 2021

A flaw was found in dnsmasq in versions before 2.85. When configured to use a specific server for a given network interface, dnsmasq uses a fixed port while forwarding queries. An attacker on the network, able to find the outgoing port used by dnsmasq, only needs to guess the random transmission ID to forge a reply and get it accepted by dnsmasq. This flaw makes a DNS Cache Poisoning attack much easier. The highest threat from this vulnerability is to data integrity.

Priority

Medium

CVSS 3 base score: 4.0

Status

Package Release Status
dnsmasq
Launchpad, Ubuntu, Debian
Upstream
Released (2.85)
Ubuntu 21.04 (Hirsute Hippo) Needed

Ubuntu 20.10 (Groovy Gorilla) Needed

Ubuntu 20.04 LTS (Focal Fossa) Needed

Ubuntu 18.04 LTS (Bionic Beaver) Needed

Ubuntu 16.04 ESM (Xenial Xerus) Needed

Ubuntu 14.04 ESM (Trusty Tahr) Needs triage

Patches:
Upstream: https://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commit;h=74d4fcd756a85bc1823232ea74334f7ccfb9d5d2