Cracking Passwords with Ophcrack
Due: Oct 22.

 

 

 

Warning: These instructions are meant to provide you training with security issues. You are advised to implement this project on Virtual Machines Stealing passwords from any other real machine that is not yours, is not a good idea – it is a criminal offense.

 

 

This is a experiment to crack Windows XP passwords with Ophcrack.

 

To do this, first download, the ISO file for Ophcrack (Live CD) [not the installable EXE] from - http://ophcrack.sourceforge.net/ . This is an ISO file.
You can also get it from Raghu in the lab. Keep this file on a computer where you will run  VMWare.

 

Also, read about Ophcrack and how to use it on the web. Familiarize yourself with what you are doing. A good set of instructions are at:

http://lifehacker.com/software/password-recovery/screenshot-tour-how-to-crack-a-windows-password-with-ophcrack-live-cd-232963.php

 

 

Now start a Windows XP virtual machine.

  1. Create several accounts, and give them passwords, some simple, some harder.
  2. Shut down XP
  3. Once the machine shuts off you should be able to view the settings for the VM from the VMware console. Under edit settings, add another CD/DVD drive.
  4. When you hit the next button, it asks you to select a drive connection make it use an ISO image. Provide it with the location of ISO image for Ophcrack.
  5. Now restart the machine, you may need to press F2 to enter the BIOS of VMware and change the boot priority so that the machine boots from the ISO image.

 

Continue starting your machine from the ISO. The machine loads up under a LINUX environment. It will load a screen where it shows you the account names. Let the program run for enough time till it displays all(?) the passwords on the XP machine.

 

Report:

Submit a report (1 page)

  1. What did you learn?
  2. What are the passwords that were cracked and how long did it take?
  3. What passwords are uncrackable?

 

Challenge question(s):

  1. How do you make Ophcrak have a larger domain of passwords it can crack?
  2. What is the time/space tradeoff, that is how do we determine what to do when a password is not being cracked in reasonable time? (look for more rainbow tables, find out how they are made).