Security Distro

VMware

Is Multi-platform Virtualization Software that lets you run one operating system within another, which is quite useful for security researchers who commonly need to test code, exploits, etc on multipl

 

Knoppix

Is a general-purpose bootable distro on CD or DVD.
 

Inside Security Rescue Toolkit

Is a complete, bootable linux system. INSERT comes with a graphical user interface running the fluxbox window manager while still being sufficiently small enough to fit on a credit card-sized CD-ROM.
 

Helix

Is another Linux distro used for Computer Forensics. It is a customized distribution of the Knoppix Live Linux CD.

 

Bastille

Is a security hardening script for Linux, Mac OS X, and HP-UX. Its function is to "lock down" an operating system, and configuring the system for increased security.

 

BackTrack

Is a Linux distribution Pen testing toolkit. It is an excellent CD bootable Linux distribution. It has a huge variety of Security and Forensics tools and a rich development environment.