Railgun—converting Ruby into a weapon

In the previous recipe, we saw the use of the Meterpreter API to run Ruby scripts. Let's take that a step further. Suppose we want to make remote API calls on the victim machine; what is the simplest method? Railgun is the obvious answer. It is a Meterpreter extension that allows an attacker to call DLL functions directly. Most often, it is used to make calls to the Windows API, but we can call any DLL on the victim's machine.

Getting ready

To start using Railgun, we will require an active Meterpreter session on our target machine. To start the Ruby interpreter, we will use the irb command, as discussed in the previous recipe:

meterpreter > irb
[*] Starting IRB shell
[*] The ...