CVE-2026-19401 Affecting nsd package, versions <4.15.1-1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-DEBIANUNSTABLE-NSD-19425047
- published29 Aug 2026
- disclosed26 Aug 2026
Introduced: 26 Aug 2026
NewCVE-2026-19401 (opens in a new tab)How to fix?
Upgrade Debian:unstable nsd to version 4.15.1-1 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream nsd package and not the nsd package as distributed by Debian.
See How to fix? for Debian:unstable relevant fixed versions and status.
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.