Apache Tomcat - An open source software implementation of the Java Servlet and JavaServer Pages technologies
Nessus - Nessus Professional is a security platform designed for businesses who want to protect the security of themselves, their clients, and their customers.
Microsoft IIS - Internet Information Services is a web server for Microsoft Windows
Tenable.io - Tenable.io Cyber Exposure platform helps to protect any asset on any computing platform and eliminate blind spots.
Apache HTTP Server - Apache httpd has been the most popular web server on the Internet since April 1996
AlienVault USM (from AT&T Cybersecurity) - AlienVault USM Anywhere delivers powerful threat detection, incident response, and compliance management for cloud, on-premises, and hybrid environments.