CVE-2020-12667
HIGHKnot Resolver < 5.1.1 - Uncontrolled Resource Consumption via NXNSAttack
Title source: llmDescription
Knot Resolver before 5.1.1 allows traffic amplification via a crafted DNS answer from an attacker-controlled server, aka an "NXNSAttack" issue. This is triggered by random subdomains in the NSDNAME in NS records.
References (6)
Core 6
Core References
Mailing List, Third Party Advisory mailing-list
http://www.openwall.com/lists/oss-security/2020/05/19/2
Mailing List, Third Party Advisory vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/76Y4FITMOH6RVPWAANGV7NB2ZHPJJGDQ/
Mailing List mailing-list
https://lists.debian.org/debian-lts-announce/2024/04/msg00017.html
Technical Description, Third Party Advisory
http://cyber-security-group.cs.tau.ac.il/#
Technical Description, Vendor Advisory
https://en.blog.nic.cz/2020/05/19/nxnsattack-upgrade-resolvers-to-stop-new-kind-of-random-subdomain-attack/
Release Notes, Vendor Advisory
https://www.knot-resolver.cz/2020-05-19-knot-resolver-5.1.1.html
Scores
CVSS v3
7.5
EPSS
0.0262
EPSS Percentile
83.5%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-400
Status
published
Products (1)
nic/knot_resolver
< 5.1.1
Published
May 19, 2020
Tracked Since
Feb 18, 2026