CVE-2019-19331
mediumpriority · track · 31EPSS 0.021 · 82 %ileEUUSEPSS · scored 2026-10-27
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).
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (10)
External citations — patches, advisories, analysis.
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-19331cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2019-19331cnnvd
- https://vigilance.fr/vulnerability/Knot-Resolver-denial-of-service-via-DNS-Replies-Many-RR-31146cnnvd
- https://www.knot-resolver.cz/2019-12-04-knot-resolver-4.3.0.htmlcnnvd
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-19331enisa_euvd
- https://lists.debian.org/debian-lts-announce/2024/04/msg00017.htmlenisa_euvd
- https://www.knot-resolver.cz/2019-12-04-knot-resolver-4.3.0.htmlenisa_euvd
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-19331ExploitIssue TrackingPatchnvd
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