Note: I’ve not tried this on anything else so YMMV if you try this on 5r1 or less.
Fire open a terminal window and as root type:
apt-get remove nessus
This will remove the old v4.4.1 version from your backtrack instance and stop any nastyness occurring when you run the install with the two versions clashing.
Now head to http://www.nessus.org and grab yourself a copy of the latest version.
If you’re lucky enough to have a professional feed, great stuff.
If it’s your first time dealing with nessus, you’ll need to register for a homefeed so follow the steps online.
Download the package labeled as: Nessus-5.0.0-ubuntu910_amd64.deb (if you’ve a 64bit machine, else go for i386). I’ve not tested any other packages but I know the above one worked for me.
now back within the terminal window and in the location you saved the file to type:
dpkg -i Nessus-5.0.0-ubuntu910_amd64.deb
and watch as it magically installs everything you need. Upon completion nessus should be callable from the path.
To confirm the version number, it should come back at 5.0.0
Then using the code either for your professional feed or home feed register your nessus install:
nessus-fetch --register SERIAL_NUMBER_YOU_HAVE
Wait and it should confirm a successful registration and download the plugins.
Now just fire up nessus (first time after an update it takes an age as it unpacks and loads the plugins) and you’re away.
Not quite. What will come next is a guide as to how on earth you get Flash working in the onboard firefox on BT5R2.
Then, you should be all set for nessus scanning from your backtrack installation.