- Download and install VirtualBox from https://www.virtualbox.org/wiki/Downloads.
- Download the 64-bit .iso file for Ubuntu 16.04 Desktop from https://www.ubuntu.com/download/desktop/thank-you?country=US&version=16.04.1&architecture=amd64.
- Create a new VM in VirtualBox, then attach the ISO file for Ubuntu as a virtual DVD and boot it.
- Complete the installation process for Ubuntu.
- Once Ubuntu is installed and has rebooted, open a Terminal.
- Run this command:
wget https://ctf.hackucf.org/ctf_vm_setup.sh && bash ctf_vm_setup.sh
- When this script finishes, it'll give you instructions on how to install VirtualBox Guest additions. Follow those instructions.
And that's basically all you need to get your CTF environment up and running!