Medusa and commands in Backtrack

Medusa

Medusa is a log-in brute forcer that attempts to gain access to remote services by guessing at the user password. Medusa is capable of attacking a large number of remote services including FTP, HTTP, MySQL, Telnet, VNC, Web Form, and more. In order to use Medusa, you need several pieces of information including the target IP address, a username or username list that you are attempting to log in as, a password or dictionary file containing multiple passwords to use when logging in, and the name of the service you are attempting to authenticate with.
Medusa comes installed on Backtrack 5. However, if you are using a different version of backtrack without Medusa type:
apt-get update
apt-get install medusa
When using online password crackers, the potential for success can be greatly
increased if you combine this attack with information gathered from reconnaissance and scanning. An example of this is when you find usernames, passwords, and email addresses. Programs like Medusa will take a username and password list and keep guessing until it uses all the passwords. Be aware that some remote access systems employ a password throttling technique that can limit the number of unsuccessful log-ins you are allowed. Your IP address can be blocked or the username can be locked out if you enter too many incorrect guesses.
Backtrack includes a few word lists that you can use for your brute forcing adventures. You can find one list at:
/pentest/passwords/wordlists/

In order to execute the brute-force attack, you open a terminal and type the following:

medusa –h target_ip –u username –P path_to_password_dictionary –M service_to_attack
“-h” is used to specify the IP address of the target host. The “-u” is used for a single username that Medusa will use to attempt log-ins. “-P” is used to specify an entire list containing multiple passwords. The “-P” needs to be followed by the actual location or path to the dictionary file. The “-M” switch is used to specify which service we want to attack.

Here I launch an attack against my own ssh server.

More to come!

Updating and Linux Commands

Before we can begin hacking away with Backtrack, we first must do a little updating. Backtrack is contains a ton of programs and frameworks such as Metasploit, which is constantly updated. You may have to update your tools two or three times a week. Also, if you are new to Linux operating systems, you will have to learn how to use the terminal and basic Linux commands. So let’s get started.

Updating Backtrack 5

Since Backtrack is based on Ubuntu 10.04 (which is based on Debian), it has the apt-get  command. Apt-get is a powerful command-line tool that is used for installing new software packages, updating, and even upgrading the operating system. We will use this command to get the latest version of Backtrack. After logging in to Backtrack, open a terminal (Applications > Accessories > Terminal):
Then issue the following command:
root@bt:~# apt-get update && apt-get upgrade && apt-get dist-upgrade
The command will then select all the new updates for Backtrack, and after a short time it will ask you to continue. Press ‘y’ for yes.
If you just installed Backtrack, this update will take about 15-20 minutes. Keep an eye on the console for when it asks “Do you want to continue?”. Again, press ‘y’ for yes. You will want to run the command apt-get upgrade && apt-get upgrade once a week to keep Backtrack up-to-date.

Linux Commands

There are many Linux commands, and they can be used in various combinations. I will list a the basic ones which you should learn if you are new to Linux and Backtrack. Most commands can have parameters which gives them added functionality. To see the parameters, or to learn what a command does, add -h or –help after them.
(Example: cat –help).

• cat – This is command is short for “Concatenate” and prints out the standard output
  Example: cat filename
• cd – Change Director. Switches the current directory you are in.
  Example: cd foldername
  Example: cd root/Desktop/
• clear – clears the terminal screen.
• ls – List the files and folders within the current directory. (Note that is ‘L’ not ‘i’)
• mkdir – Make Directory. Create a new directory of the given name
  Example: mkdir myFolder
• ping – Send a packet to a host and waits for a response.
  Example: ping -c 4 google.com (The -c 4 parameter limits the ping to 4 counts).
• rm – Remove. Removes a file or folder.
  Example: rm filename