Rapid7’s 2026 Global Cybersecurity Summit is now available on-demand.Watch sessions.
Rapid7

vulnerability

Ubuntu: USN-7047-1 (CVE-2019-19331): Knot Resolver vulnerabilities

Severity
5
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:P)
Published
Dec 16, 2019
Added
Oct 2, 2024
Modified
Mar 27, 2026

Description

knot-resolver before version 4.3.0 is vulnerable to denial of service through high CPU utilization. DNS replies with very many resource records might be processed very inefficiently, in extreme cases taking even several CPU seconds for each such uncached message. For example, a few thousand A records can be squashed into one DNS message (limit is 64kB).

Solution

ubuntu-upgrade-knot-resolver
Title
Rapid7 Labs

2026 Global Threat Landscape Report

The predictive window has collapsed. Exploitation follows disclosure in days. See how attackers are accelerating and how to stay ahead.