Guide to Whitebox Pentest

Mehul Panchal

Reading code is like a Pentester’s superpower. Although it takes a lot of time to get good at it just like any other skill.

But once you know how to read and understand code efficiently in multiple languages, you can leverage that superpower to find the vulnerabilities that couldn’t have been found.

These are the steps to make sure to make the best out of your practice of reading code:

1. Know how to code and know Computer Science.

Reading the code comes after knowing how to code. Most of the hackers out there preach that you don’t need to know how to code to be a hacker and that’s absolutely a lie. Learning how to code should be the first thing you have to do in your journey to become a hacker. Learn to code not in one but multiple languages. First, learn to write code in Python and then C++. This way you’d understand programming concepts, low-level and object-oriented stuff. On top of this, you should know Computer Science concepts in depth. All of this is important to have technical mastery in the field of CyberSecurity.

2. Know how to Pentest BlackBox applications

Having done some BlackBox Pentests is a great way to have knowledge of vulnerabilities that could ever exist in the applications. If you know what vulnerabilities could possibly exist in a BlackBox application, then certainly you know what vulnerabilities could exist in a WhiteBox Application after you have read the code.

3. Setting up the environment

You could be the best hacker in the world, you could be James Bond of the hackers’ world. But you can only perform so much without a perfect environment setup to start with.

Here is the essential list of what you’ll need to set to read code:

  • The application should be running with debugging enabled.
  • A perfect IDE connected to the debugging port of the application.
  • Set a breakpoint
  • Test if the IDE stops at the breakpoint

4. Reading and Understanding the code

Ideally, the IDE will outline the functions of the application in the code. Go through each function one by one, by using the corresponding functionality in the application all while setting breakpoints, to understand their role in the application.

After understanding the functions, you should be able to understand the developer’s writing pattern and business logic. Also, You should be able to understand the role of each function in the code.

Finding vulnerabilities becomes so much easier when you have a complete map of the application’s functions in mind.

5. Finding the Vulnerabilities

If you have done all the above steps correctly, then you’ll be automatically figuring out the possibilities of vulnerabilities.

As this is just an overview of WhiteBox Pentest, I’ll going over every step in detail. Stay Tuned!

This article was updated on January 15, 2024

I'm Mehul Panchal (𝕏: @0daySecured), an Ethical Hacker and seasoned penetration tester with over 6.5 years of hands-on experience in identifying vulnerabilities and fortifying security for a diverse range of corporate clients. Holding both the OSCP and OSWE certifications, I bring a deep understanding of offensive security techniques and a commitment to staying ahead of the curve in the ever-evolving landscape of cybersecurity.

Currently based in the beautiful city, Prague. I provide my services for Forbes Top 500 ranked clients at a leading cybersecurity firm. My journey in this field began with self-learning computer science and OSCP certification, a foundation that has been significantly strengthened by continuous learning and practical application. My technical expertise is complemented by robust skills in consulting and technical writing, allowing me to effectively communicate the value of security solutions to stakeholders at all levels.