Enumeration and Shell
In most cases, a firewall will block our access to the internal network,
blocking access to everything except publicly-available services
like web and email servers.
This leaves us with two common avenues of attack: social engineering through email
or a serverside attack.
If our client has no preference, we would perform enumeration to determine
the best option.
In a real-world test, we will often begin enumeration with open source intelligence
gathering and exploration of publicly-available resources.
However, we have made some simplifications for this module.
The target network only consists of three machines and we have not installed a
firewall between our Kali machine and the target machines.
In addition, we will be skipping many aspects of the often-extensive open source
reconnaissance and information gathering phases,
which are difficult to recreate in this environment.