Vulnerability in Nlnet Labs Nsd

CVE-2026-19538

The BLOCKED access control list items that are evaluated to deny access on the the proxy protocol port can be bypassed completely when connecting over TCP or TLS and sending the query twice on connection that is kept open.

EPSS: 0.004 (28.1th percentile) — read the EPSS interpretation.

Affected products

Weakness classification (CWE)

References