High severity · published Dec 16, 2019
CVE-2019-19331
knot-resolver before version 4.3.0 is vulnerable to denial of service through high CPU utilization
7.5
CVSS
2.1%
EPSS
No
On KEV
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).
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.1% · higher than 82% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
10.0 · source: NVD
KR
Knot Resolver · Nic
before 4.3.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-19331
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-19331
Exploit
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-19331
lists.debian.org
https://lists.debian.org/debian-lts-announce/2024/04/msg00017.html
Release Notes
https://www.knot-resolver.cz/2019-12-04-knot-resolver-4.3.0.html
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