BackTrack 4 is now a fully fledged OS with Ubuntu as the underlying OS. What follows is a tutorial on how to install Nessus 4.2 on BackTrack 4 Vmware. One of the major changes in Nessus 4.2 is that the client software that was used previously on port 1241 is now replaced by a web application on port 8834.
If you need the vmware image of backtrack, you can grab it from here: http://www.backtrack-linux.org/downloads/
Login to back Track
Login:root
password:toor </p>
To start the GUI in backtrack 4 use startx.
By default the network device is off, you need to enable it. In my case we can just use dhclient but if you want to use a static ip you can just set it with ifconfig
dhclient eth0
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Now you will need to grab the installer for Nessus. Go to http://www.nessus.org/download/ and grab the ubuntu 8.10 version. Save the file to your desktop and open a shell.
Install the package with:
dpkg -i <strong>[package-name]</strong>
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Now that the software is installed, you need to add a user:
/opt/nessus/sbin/nessus-adduser
Answer the questions and you will create a new user and define the users password.</p>
Now to make Nessus actually useful you need to register it so that you can get current plug-ins, you can do that at http://www.nessus.org/plugins/index.php?view=register-info.
After this you will get an email that contains your user registration code, use the the following command to activate it.
/opt/nessus/bin/nessus-fetch --register <strong>[your key]</strong>
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When you run the command above it will get the most recent plugins. Depending on your connection it may take a few min, so just be patient.
Now start the Nessus service
/etc/init.d/nessusd start
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To make sure the Nessus is up and working you can use:
ps -aux|grep nessusd; netstat -nat|grep 8834
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As I mentioned above, the new version of Nessus uses a web GUI instead of the old client application. You will need to load firefox and navigate to https://127.0.0.1:8834
When you get to the login screen, use the same user name and password that you created above.
That's it, by default firefox will block the scripts from running, you will need to have noscript allow the scripts in order for it to function correctly.