CVE-2020-12667 Information

Description

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Reference

http://cyber-security-group.cs.tau.ac.il/ http://www.openwall.com/lists/oss-security/2020/05/19/2 https://en.blog.nic.cz/2020/05/19/nxnsattack-upgrade-resolvers-to-stop-new-kind-of-random-subdomain-attack/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/76Y4FITMOH6RVPWAANGV7NB2ZHPJJGDQ/ https://www.knot-resolver.cz/2020-05-19-knot-resolver-5.1.1.html

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

7.5