Reverse engineering (RE) can seem intimidating at first, but with the right approach, anyone can start understanding how programs and malware work at a low level. This guide is for beginners who want to get started with reverse engineering Windows binaries, shellcode, and compiled C/C++ programs.

Why Learn Reverse Engineering?

• Understand what programs do under the hood.
• Analyze malware safely in a controlled environment.
• Develop debugging, problem-solving, and low-level programming skills.

Key Concepts to Learn First

Before diving in, familiarize yourself with these fundamental concepts:

• Registers: CPU storage locations like EAX, EBX, RAX, RCX that hold data temporarily.
• Stack: A memory structure used for function calls, local variables, and return addresses.
• Opcodes: Raw machine code bytes the CPU executes (like 0x90 or 0x31).
• Mnemonics: Human-readable assembly instructions corresponding to opcodes (like NOP or XOR EAX, EAX).
• Calling Conventions: How functions pass arguments and return values (important for understanding function calls in assembly).

Recommended Learning Resources

Here are some of the best beginner-friendly resources to start your reverse engineering journey:

• Reverse Engineering for Beginners by Dennis Yurichev – Free comprehensive book covering registers, memory, assembly, and reversing exercises. https://yurichev.com/writings/RE4B-EN.pdf
• OpenSecurityTraining – Intro x86/x86-64 Courses – Recorded lectures + slides that teach the architecture and common instructions used in reversing. https://opensecuritytraining.info/IntroX86.html
• Malware Unicorn – Reverse Engineering 101 – Hands-on workshop with practical Windows binary reversing exercises. https://malwareunicorn.org/workshops/re101.html
• Seanthegeek’s x86 Assembly Primer – Blog posts with short, practical examples of the most common instructions. https://www.seanthegeek.com/x86-assembly-primer
• Awesome Reversing GitHub Collection – Curated resources including tutorials, tools, and CTF exercises. https://github.com/0x90d/awesome-reversing

Suggested Beginner Workflow

Once you’re ready to start practicing, here’s a simple loop to follow:

1. Read a short chapter or blog post about assembly and CPU basics.
2. Write a tiny C function (like adding two numbers) and compile it.
3. Open the compiled binary in a disassembler (Visual Studio Disassembly, Ghidra, or IDA Free).
4. Step through the instructions using a debugger, watching registers, stack, and memory.
5. Repeat with slightly more complex code (conditionals, loops, local variables) to build intuition.

Tools You’ll Need

• Visual Studio – Build, debug, and view disassembly.
• Ghidra – Free, interactive disassembler and decompiler. https://ghidra-sre.org/
• x64dbg – Windows debugger for native binaries. https://x64dbg.com
• PE Viewers: PE-bear, CFF Explorer for inspecting PE structure. https://www.softpedia.com/get/Programming/File-Editors/PE-bear.shtml https://www.ntcore.com/exsuite.php

Final Thoughts

Reverse engineering is challenging at first, but every hour you spend stepping through a tiny binary or inspecting a resource in memory builds intuition. Focus on small, concrete exercises, learn the core instructions, and gradually expand your understanding. With consistent practice, reading assembly and understanding what’s happening in memory will become second nature.

Remember: always practice in a controlled environment (VM or sandbox) and never run unknown binaries on your main system.