CVE-2026-18916: medium-severity vulnerability in NLnet Labs NSD
Remote TCP DoS by throttling the TCP receive window
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.9epss 0.5%
Any remote client can crash a NSD serve child, by throttling the TCP receive window after a TCP query. By continuously crashing the serve childs, the remote client can denial all TCP service to this NSD instance.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Affected products
NLnet Labs · NSDRelated CVEs — NLnet Labs NSD
In the same product, most dangerous first.
CVE-2020-28935—Local symlink attack in Unbound and NSDEPSS 0.5%CVE-2026-12244HIGHHeap overflow and crash with crafted SVCB RREPSS 0.5%CVE-2026-19401HIGHRemote UDP DoS by sending multiple DNS Cookie optionsEPSS 0.5%CVE-2026-12245HIGHDenial of DNS over TLS service by any DoT clientEPSS 0.5%CVE-2026-12246HIGHOut of bounds stack write with crafted APL RREPSS 0.4%CVE-2026-19538HIGHBypass of BLOCKED ACL items on proxy protocol port over TCP or TLSEPSS 0.4%