CVE-2026-19401

Name
CVE-2026-19401
Description
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.
NVD Severity
unknown
Other trackers
CVE, NVD, CERT, CVE Details, CIRCL, Arch Linux, Debian, Red Hat, Ubuntu, Gentoo, SUSE (Bugzilla), SUSE (CVE), Mageia
Mailing lists
oss-security, full-disclosure, bugtraq
Exploits
Exploit DB, Metasploit
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
sep@nlnetlabs.nl https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-19401.txt

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:nlnetlabs:nsd:*:*:*:*:*:*:*:* nsd >= 4.3.7 < 4.15.1

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
nsd edge-main 4.15.1-r0 Natanael Copa <ncopa@alpinelinux.org> fixed
nsd edge-main 4.15.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.14.3-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.14.2-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.14.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.14.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.13.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.12.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.11.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.11.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.10.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.24-main 4.14.3-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.24-main 4.14.2-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.23-main 4.13.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.22-main 4.12.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.21-main 4.11.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.21-main 4.11.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.21-main 4.10.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.20-main 4.9.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.19-main 4.7.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable