CVE-2019-19331

Publication date 16 December 2019

Last updated 2 October 2024

Ubuntu priority

Cvss 3 Severity Score

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).

Status

Show unmaintained releases

Package	Ubuntu Release	Status
knot-resolver	24.10 oracular	Not affected
	24.04 LTS noble	Not affected
	23.10 mantic	Not affected
	23.04 lunar	Not affected
	22.10 kinetic	Not affected
	22.04 LTS jammy	Not affected
	21.10 impish	Ignored end of life
	21.04 hirsute	Ignored end of life
	20.10 groovy	Ignored end of life
	20.04 LTS focal	Fixed 3.2.1-3ubuntu2.2
	19.10 eoan	Ignored end of life
	19.04 disco	Ignored end of life
	18.04 LTS bionic	Vulnerable
	16.04 LTS xenial	Vulnerable
	14.04 LTS trusty	Not in release

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
knot-resolver	Upstream: https://gitlab.nic.cz/knot/knot-resolver/-/merge_requests/903 Upstream: https://gitlab.nic.cz/knot/knot-resolver/-/merge_requests/899

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

USN-7047-1
Knot Resolver vulnerabilities
1 October 2024