Pentesting Workshop with Kali Linux #2

<br /><br />INTRODUCTION<br /><br />Dear reader, welcome to this new edition of the Pentesting saga of the Underc0de forum. I am MagoAstral and I am pleased to be the tutor who will develop this edition. Like you, I am an enthusiast of computer security and insecurity, and I think it is very timely to create a manual talking a bit about that toolbox the pentester usually uses in their audits, and what better moment than with the release of the new version of Kali Linux.<br /><br />I must say this will be an installation from the perspective of a novice user. Before starting with the topic, I will list the requirements to carry out the phases that will be developed in this workshop or manual:<br /><br />•   Virtualization software; on this occasion VMware Workstation 11 will be used<br />•   Kali Linux version 2.0 image<br />•   10 GB free for the system installation<br />•   768 MB of RAM for Gnome 3<br /><br />These would be the recommended requirements; it is worth noting that the desktop environment will be changed throughout the manual to a lighter one (xfce), this step is a matter of taste and comfort. If you feel confident with Gnome, you can stay with Gnome, I am nobody to push you to use an environment you don't know, although I do advise you to try it.<br /><br />As we know, when performing a penetration test, time is a factor that plays against us and therefore it is very important to automate the process. That is why we use a distribution oriented to that task, since it will normally supply us with any tool we need. Personally I like the quote: "What matters is not the time you have, but how you use that time", and that is where Kali  Linux comes into play.<br /><br />Before starting the installation let's talk a bit about Kali Linux. Obviously it is a distribution designed for computer security and audits, which in turn is based on Debian (GNU/Linux) and was founded by Offensive Security Ltd.<br /><br />Its initial release was on March 13, 2013 and it is considered the successor of BackTrack (those who have been in the pentest world for a little while will have worked with it); the second version of Kali Linux was released on August 11, 2015. An important fact to highlight is that, since Kali Linux has various security and auditing tools, it is recommended to run it as a superuser (root) to avoid conflicts. <br />From my point of view I recommend using it virtualized and on an isolated network segment when auditing your labs, since it is not advisable to expose those machines to the network of networks; obviously if you are going to work with this system continuously you will see that many auditors have it as their base system, but if you are in the initial stages, that is my recommendation.<br /><br />Regarding the changes in Kali Linux, its new version has a 4.0 kernel based on Debian Jessie, they have obviously updated their arsenal of tools, and it has become a rolling release distribution. As for the desktop environment, we now have Gnome 3 -but as I said before- I lean towards XFCE, so I will show how to install it.<br /><br />With nothing more to add, we can now proceed to download the system image; for that we go to: Los enlaces son solo para miembros. Registrate o iniciá sesión<br /><br />Once downloaded I would recommend verifying that it is the original image, so we will proceed to check its SHA-1 hash:<br /><br /><br /><br />As we can see the hashes match, therefore we can now begin creating the virtual machine and installing Kali Linux.<br /><br />CREATING THE VIRTUAL MACHINE: VMWARE<br /><br />We will start by opening VMware and creating a new virtual machine; this time we will select typical configuration and load the ISO like this:<br /><br /><br /><br />The next step, continuing with the installation, is to select Debian 7.x and the corresponding architecture, in my case 64 bit (if you have the Debian 8 option, select it, since it would correspond to Debian Jessie):<br /><br /><br /><br />We continue by choosing the machine name, which in my case will be Kali Linux:<br /><br /><br /><br />In the next window it asks us to specify the virtual disk size; in my case I will set 25 GB and leave the second option selected as follows:<br /><br /><br /><br />Then all that's left is to finish the creation process and we will have our virtual machine. Finally we are going to configure the network; in my case I will set it to bridged adapter mode and add a little more random access memory (RAM). The final result would be:<br /><br /><br /><br />At this point we have finished creating and configuring our virtual machine. In the next section we will proceed to install Kali Linux. <br /><br /><br />INSTALLING KALI LINUX<br /><br />Once the machine boots we will select the graphical install:<br /><br /><br /><br />When we enter graphical mode we will select our keyboard, location and language (I will skip these steps since it is just clicking). Next it will ask for our hostname; obviously you can put whatever you want:<br /><br /><br /><br />Then it will ask for a domain name, which we will leave blank, and after that it's time to fill in the superuser password.<br /><br /><br /><br />We will continue by configuring the clock to match our time zone and we will reach the disk partitioning section. As I said, this will be an installation from a novice's perspective, so we will select guided - use entire disk:<br /><br /><br /><br />We will select the only disk we have and then put all files in one partition:<br /><br /><br /><br />We finish partitioning and write the changes to disk:<br /><br /><br /><br />Then we would confirm the operation and the system installation process would begin. Next it asks whether we want to use a network mirror; we will leave it at yes since it is essential for installing from the Kali Linux repositories:<br /><br /><br /><br />The proxy is optional; in my case I will leave it blank. Now it's time to install GRUB and we will install it to the master boot record, so we select the default option:<br /><br /><br /><br />In this step we will select the device where we are going to install the boot loader:<br /><br /><br /><br />And after selecting it we will have successfully finished installing our Kali Linux:<br /><br /><br /><br />After rebooting the system and entering our credentials (root) the final result will be:<br /><br /><br /><br />Perfect! Now we have our Kali Linux ready to use, but obviously we still have the post-installation process, which is almost as important as, or more important than, the installation process. <br />The first thing will be to check that our sources.list contains all the Kali repositories (Los enlaces son solo para miembros. Registrate o iniciá sesión); for that we will simply run:<br /><br />

cat /etc/apt/sources.list

<br /><br />As we can see everything is correct:<br /><br /><br /><br />So now it's time to update our Kali Linux and keep it up to date, so we will run:<br /><br />

apt-get clean && apt-get update && apt-get upgrade –y && apt-get dist-upgrade –y

<br /><br />My terminal output:<br /><br /><br /><br />After this, we can proceed to install the respective Linux headers:<br /><br />

aptitude install build-essential Linux-headers-$(uname –r)

<br /><br /><br /><br />Once the headers are installed, we can proceed to insert the VMware tools to freely adjust our system's resolution: <br /><br /><br /><br />After inserting the VMware tools, we proceed to extract the file, enter the directory and install them:<br /><br /><br /><br />Once the installation of these tools is finished, we will be ready to adjust the display:<br /><br /><br /><br />This concludes the basic post-installation part. <br /><br /><br />INSTALLING XFCE<br /><br />We are going to install another desktop environment; this time, as I said before, we will install XFCE, and for that we type in our terminal:<br /><br />

apt-get install kali-defaults kali-root-login desktop-base xfce4 xfce4-places-plugin xfce4-goodies

<br /><br /><br /><br />Now we will install lightdm using the following syntax:<br /><br />

apt-get install lightdm xfce4

<br /><br />And we will configure the session from:<br /><br />

/usr/share/xsessions/

<br /><br />We will use our favorite editor, in my case nano:<br /><br /><br /><br />After editing the session manager our xfce should start; if we reboot we will see that the changes have been applied correctly:<br /><br /><br /><br />The final result:<br /><br /><br /><br />I would leave it here since I don't like to overload the system with unnecessary effects or customize it, but since I admit it doesn't look very attractive visually, let's customize the system a bit. To customize our xfce we can go to: Los enlaces son solo para miembros. Registrate o iniciá sesión , where we will find a variety of wallpapers, icons, themes, etc... <br /><br />I will assume you know how to install themes and icons, since it is simply moving them to the path /usr/share/themes or /usr/share/icons (depending on what you are installing).<br /><br />Then in the applications menu we go to settings and in appearance we select the installed themes and icons.<br /><br />And after this customization process, you could end up with something similar to the following image: <br /><br /><br /><br />With this I conclude this installment; it has been a pleasure guiding you through this process. <br /><br /><br /><br />