CVE-1999-0454

High severity, CVSS 10.0. EPSS: 2.7% chance of exploitation in the next 30 days.

A remote attacker can sometimes identify the operating system of a host based on how it reacts to some IP or ICMP packets, using a tool such as nmap or queso.

Published 1999-01-01. Last modified 2026-06-16.