CVE-2026-18916

High

Description

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.

SeverityHigh

CVSS7.5

Exploit probability—

ProductNlnetlabs Nsd

PublishedAug 26, 2026

First seenAug 26, 2026

Weakness typeCWE-191CWE-191

How to fix

Update

nlnetlabs nsd4.15.1 or later

Vendor advisories

nlnetlabs.nl/downloads/nsd/CVE-2026-18916.txt

Affected products

Product	Affected versions	Fixed in
nlnetlabs nsd	3.2.11 ≤ v < 4.15.1	4.15.1

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