So, in this quick video (made ages ago for the talk I gave at CampusCon), I demonstrate the use of an ARP Poisoning attack to redirect someone elses traffic through my computer, then I sniff thier traffic. In a later blog post I will write more about MiTM and ARP Poisoning, but for now, check out this video. It uses Nemesis, which we covered in my last post, to function…
Ok. Nemesis is a very powerful Packet Crafting/Injection tool for Unix based systems. I have heard that ALLEGEDLY it can be installed/ran on Windows also, but never felt like trying, as I do not use Windows nor is Windows much good for ANYTHING to do with sockets.
Nemesis is similar to tools like “hping” in that you can customize the packet you want to send, and send it. Very useful for playing with low level protocols, and incredible if you want to learn more about the network layer stuff.
For more information on Nemesis, you can always check out the following links…
SO. How do I get Nemesis to work on Ubuntu and such?
Well, most distributions do not have it in their repositories it seems, and just because it is easy to do, let’s compile it from source.
Step One: Install Dependancies
First off we need to install the dependancies it has, so the following two commands should do the trick.
apt-get install libdnet-dev
apt-get install libpcap-dev
No screenshot should be needed here I hope…
Step Two: Install “libnet” to the /usr directory.
Now for convenience, I do my installation in the /usr directory. Don’t ask why, it just seemed right at the time.
The following commands should do this easily for you…
The first three are “preparing the build area”
The next three are “getting the sources and unpacking them”
tar -xf libnet-1.0.2a.tar.gz
The next commands “configure” and make + make install the Libnet libraries.
make && make install
So. Now that we have successfully installed Libnet (if you get some wierd errors, leave a comment and I can try help you) we can go on and install Nemesis!
Step Three: Installing Nemesis
So. This is the fun part – where we get to finally install Nemesis.
Assuming you are still in the directory “/usr/nembuild/Libnet-1.0.2a”, just “cd ..”.
Otherwise, “cd /usr/nembuild” so we are all on the same page!
So. Lets prepare our “Environment” for the Nemesis installation by getting and unpacking the sources! The following commands should do it…
tar -xf nemesis-1.4.tar.gz
So, thats everything prepared. Now for the tricky bit – making it build properly.
Note that I used very specific paths for this – this is because we HAVE to specify THESE libnet libraries!
Now for the next commands…
./configure —with-libnet-includes=/usr/nembuild/Libnet-1.0.2a/include —with-libnet-libraries=/usr/nembuild/Libnet-1.0.2a/lib
make && make install
There we go! Now for usage and such, “man nemesis” is a good place to start – they don’t make those man pages for nothing you know!
Finally, to wrap up, a screenshot of Nemesis!