CVE-2026-19401

highpriority · track · 30EPSS 0.003 · 19 %ileDEUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.28% (19th) EPSS

CVSS 7.5 · high

Is it mine?

3 products

Check your exposure

Who says so?

2 sources

cert_bund · nvd

EPSS · scored 2026-10-22

Any remote client can crash a (debugging/non-release build type) NSD serve child by sending it a special crafted message with a specially tuned number of DNS Cookie options (17 when UDP payload size is 512). By continuously crashing the serve childs, the remote client can severely hamper or, when positioned sufficiently close, deny all DNS service.

cvss

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

8.2

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.6–8.2

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

v4.08.2highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · sep@nlnetlabs.nl

v4.04.6mediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)

ssvc

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

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USCWE-617US

affected products (3)

Products and version ranges known to be affected.

OpenBSD OpenBSD 7.8all versionscert_bundDEcpe:/a:openbsd:openbsd:7.8
OpenBSD OpenBSD 7.9all versionscert_bundDEcpe:/a:openbsd:openbsd:7.9
nlnetlabs nsd4.3.7 → 4.15.1nvdUScpe:2.3:a:nlnetlabs:nsd:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-3663OpenBSD: Mehrere SchwachstellenDeutsch2026-09-29csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in OpenBSD ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, um Sicherheitsvorkehrungen zu umgehen und um einen Denial of Service Angriff durchzuführen.

sources

Which sources assert this record, and when.

cert_bund nvd NVD CVE.org MITRE

published 2026-08-26modified 2026-09-01

references (1) nvd

External citations — patches, advisories, analysis.

https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-19401.txt

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan