CVE-2019-19331

knot-resolver: knot-resolver before version 4.3.0 is vulnerable to denial of service through high CPU utilization

CVE-2019-19331 is fixed in 2 products on 1 platform, first by knot-resolver 3.2.1-3ubuntu2.2, released May 19, 2020. It is not reported as exploited. Patch Radar priority: Routine.

Routine
CVSS
n/a
Medium
Exploitation
None reported
No vendor assessment
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.0211
81st percentile

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).

Where it's fixed

ProductFixed inFixReleased
Linux
knot-resolver · Ubuntu 20.04 LTS (focal) 3.2.1-3ubuntu2.2 knot-resolver 3.2.1-3ubuntu2.2 May 19, 2020
knot-resolver-module-http · Ubuntu 20.04 LTS (focal) 3.2.1-3ubuntu2.2 knot-resolver-module-http 3.2.1-3ubuntu2.2 May 19, 2020