Kali is a Debian based Linux distribution oriented to pen testing: as a purpose specific distribution, it offers a wide amount of tools and an already set up environment to asses the weaknesses of the machines in your network and to determine how vulnerable they are to intrusion.
Downloading Kali Linux
Before we can install Linux we have to download the iso from the Kali site.As is the case with many Linux distributions nowadays, there are various Kali flavors to choose from: there are image for KDE. LXDE, Xfce, Mate, etc. We can go with the full and heavy Kali Linux, or download the light version that it is significantly smaller in size:this last one includes, of course, less software, but the user will be able to easily install any software that he/she misses using the Debian package system.
Beyond the usual options regarding the choice of desktop, and lightness of the system, it is worthwhile to remark that Kali offers also ARM images, and images for Nexus devices – the NetHunter project – opening therefore the possibility to install Kali not only in desktop/laptops, but also on mobile devices, raspberry Pi systems, etc.
Installing Kali Linux
After downloading the Kali image – in my case I settled up for the Xfce edition – we can run it as a live CD which will allow us to try the system and get a taste of it before actually installing it.
Installing Kali is a simple process that Debian users will found familiar, after all, Kali is based on Debian. Notice also that Kali is not exactly what I would all call a system for everyday usage: it is a very specific distribution, used by the companies security experts to asses weakness in the network, so it makes sense to install it in a dedicated box, or in a virtual machine that we are going to boot up when we need to do the job.
So I did set up a VM and proceeded to install the system: we start selecting the default system language, local, and keyboard layout.
Next we are asked to provider a host and domain name:
We are asked to configure a password for the root user: if we are installing Kali far from prying eyes, we can mark the check at the bottom of the screen – Show Password in Clear- .
Next we will proceed to partition the disks: as is the case with Debian, and many other distributions we will have the choices of using the full disk, free space, partitioning, keep home in a separated partition, encrypt the disks, etc.
And lastly we need to install the GRUB loader:
Finally we reboot the system in we are ready to use it.
Log into our newly installed Kali system
When loging into Kali Debian users will find themselves in a familiar environment, but if they open the applications menu they will quickly see the differences: the tools and applications installed there had not much to do with what we find in a regular system.
The webbrowser, console, text editor and some basic tools are still there, but as expected there is no office tools though, and not multimedia software; instead we got tools like these ones: nmap, – a network scanner that allows to detect the machines running in our network, and scan ip addresses for opned porst and running services-, network analyzers – Wireshark -, dns tools, etc.
Although Kali may look a it puzzling to users not familiar with the basics of pen-testing, there is some help to get users to get started:for example, the Kali site list all the tools included in the Kali distribution, and examples on how to use them.