CVE-2026-18916: Nlnetlabs Nsd

High severity, CVSS 7.5. EPSS: 0.3% chance of exploitation in the next 30 days.

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.

Affected products

• Nlnetlabs Nsd: from 3.2.11, before 4.15.1 (fixed in 4.15.1)

Published 2026-08-26. Last modified 2026-09-08.