CVE-2020-12667

mediumpriority · track · 31EPSS 0.026 · 85 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

2.61% (85th) EPSS

CVSS 5 · medium

Is it mine?

33 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · cert_bund

EPSS · scored 2026-10-27

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

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondaryexploitability 3.9 · impact 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USprimary

affected products (33)

Products and version ranges known to be affected.

Avaya Aura Application Enablement Servicesall versionscert_bundDEcpe:/a:avaya:aura_application_enablement_services:-
Avaya Aura Communication Managerall versionscert_bundDEcpe:/a:avaya:communication_manager:-
Avaya Aura Experience Portalall versionscert_bundDEcpe:/a:avaya:aura_experience_portal:-
Avaya CMSall versionscert_bundDEcpe:/a:avaya:call_management_system_server:-
Avaya Session Border Controllerall versionscert_bundDEcpe:/h:avaya:session_border_controller:-
Avaya one-Xall versionscert_bundDEcpe:/a:avaya:one-x:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
F5 BIG-IPall versionscert_bundDEcpe:/a:f5:big-ip:-
FreeBSD Project FreeBSD OSall versionscert_bundDEcpe:/o:freebsd:freebsd:-
Internet Systems Consortium BIND <9.11.19all versionscert_bundDE
Internet Systems Consortium BIND <9.14.12all versionscert_bundDE
Internet Systems Consortium BIND <9.16.3all versionscert_bundDE
Juniper Junos Space <20.3R1all versionscert_bundDE
Microsoft Windows Serverall versionscert_bundDEcpe:/o:microsoft:windows_server:-
Open Source Arch Linuxall versionscert_bundDEcpe:/o:archlinux:archlinux:-
Open Source CentOSall versionscert_bundDEcpe:/o:centos:centos:-
Open Source PowerDNS <4.1.16all versionscert_bundDE
Open Source PowerDNS <4.2.2all versionscert_bundDE
Open Source PowerDNS <4.3.1all versionscert_bundDE
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-

showing 20 of 33

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2024-0978Mehrere DNS Server: Schwachstelle ermöglicht Denial of ServiceDeutsch2020-05-19csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in mehreren DNS Server Produkten ausnutzen, um einen Denial of Service Angriff durchzuführen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund NVD CVE.org MITRE

published 2020-05-19modified 2026-06-17

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+9606 more

references (21)

External citations — patches, advisories, analysis.

scry

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