CVE-1999-1222: Microsoft Windows Nt

Medium severity, CVSS 5.0. EPSS: 5% chance of exploitation in the next 30 days.

Netbt.sys in Windows NT 4.0 allows remote malicious DNS servers to cause a denial of service (crash) by returning 0.0.0.0 as the IP address for a DNS host name lookup.

Affected products

• Microsoft Windows Nt: version 4.0 only

Published 1999-12-31. Last modified 2026-06-16.