This is a compilation of some excellent open source security projects. I will continue to update this page. Insert in comments below if you have any good reference projects or open source security tools. I am excluding the obvious ones like Metasploit and Bro for example, in this list.
Platform / Host Security
OSQuery from Facebook
Reference Link: https://osquery.io/
Github link: https://github.com/facebook/osquery
Commercial Comparison: The commercial equivalent functionality is with Tanium.
Description: osquery gives you the ability to query and log things like running processes, logged in users, password changes, usb devices, firewall exceptions, listening ports, and more. It allows you to easily ask questions about your Linux and OSX infrastructure. Whether your goal is intrusion detection, infrastructure reliability, or compliance