CVEvulnerability
CVE-2020-12667
7.5 HIGH
Official page ↗
- Status
- Modified
- Published
- 2020-05-19
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CVSS 2.0 ([email protected])
- 5.0 MEDIUM — AV:N/AC:L/Au:N/C:N/I:N/A:P
- Weaknesses
- CWE-400
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.
Affected configurations
• nic knot resolver (< 5.1.1)
Related
Weakness · CWE (1)
- CWE-400 Uncontrolled Resource Consumption weakness
References
- http://cyber-security-group.cs.tau.ac.il/# Technical Description, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2020/05/19/2 Mailing List, Third Party Advisory
- https://en.blog.nic.cz/2020/05/19/nxnsattack-upgrade-resolvers-to-stop-new-kind-of-random-subdomain-attack/ Technical Description, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2024/04/msg00017.html lists.debian.org
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/76Y4FITMOH6RVPWAANGV7NB2ZHPJJGDQ/ lists.fedoraproject.org
- https://www.knot-resolver.cz/2020-05-19-knot-resolver-5.1.1.html Release Notes, Vendor Advisory
- http://cyber-security-group.cs.tau.ac.il/# Technical Description, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2020/05/19/2 Mailing List, Third Party Advisory
- https://en.blog.nic.cz/2020/05/19/nxnsattack-upgrade-resolvers-to-stop-new-kind-of-random-subdomain-attack/ Technical Description, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2024/04/msg00017.html lists.debian.org
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/76Y4FITMOH6RVPWAANGV7NB2ZHPJJGDQ/ lists.fedoraproject.org
- https://www.knot-resolver.cz/2020-05-19-knot-resolver-5.1.1.html Release Notes, Vendor Advisory