REVERSE ENGINEERING LINUX LEARNING PROJECTS
Reverse engineering on Linux/Unix systems breaks down into these fundamental building blocks:
Software Reverse Engineering in Linux/Unix Environments
Core Concept Analysis
Reverse engineering on Linux/Unix systems breaks down into these fundamental building blocks:
| Concept Area | What You Need to Understand |
|---|---|
| ELF Binary Format | How executables are structured - headers, sections, segments, symbol tables |
| Assembly & Disassembly | Reading x86-64/ARM instructions, understanding calling conventions |
| Static Analysis | Examining binaries without execution - strings, symbols, control flow |
| Dynamic Analysis | Tracing execution - syscalls, library calls, memory access |
| Debugging | Breakpoints, memory inspection, register manipulation |
| ptrace Internals | How debuggers actually control processes at the kernel level |
| Binary Patching | Modifying executables to change behavior |
| Anti-RE Techniques | Obfuscation, packing, anti-debugging tricks |
Project 1: ELF Binary Inspector
- File: REVERSE_ENGINEERING_LINUX_LEARNING_PROJECTS.md
- Programming Language: C
- Coolness Level: Level 4: Hardcore Tech Flex
- Business Potential: 1. The âResume Goldâ
- Difficulty: Level 3: Advanced
- Knowledge Area: Reverse Engineering / Systems Programming
- Software or Tool: readelf
- Main Book: âPractical Binary Analysisâ by Dennis Andriesse
What youâll build: A command-line tool that parses and displays the internal structure of ELF executablesâheaders, sections, symbols, and dependenciesâlike a simplified readelf.
Why it teaches reverse engineering: Every RE task starts with understanding the binary format. By parsing ELF yourself, youâll internalize how Linux organizes executable code, where symbols live, how dynamic linking works, and what information is available before ever running a program.
Core challenges youâll face:
- Parsing the ELF header and understanding magic bytes, architecture flags, entry points
- Navigating section headers vs program headers (static vs runtime view)
- Extracting and demangling symbol tables (.symtab, .dynsym)
- Understanding relocations and how dynamic linking resolves addresses
Key Concepts:
- ELF Structure: âPractical Binary Analysisâ Ch. 2-3 - Dennis Andriesse
- Binary Formats: âComputer Systems: A Programmerâs Perspectiveâ Ch. 7 - Bryant & OâHallaron
- Linking & Loading: âThe Linux Programming Interfaceâ Ch. 41-42 - Michael Kerrisk
Difficulty: Intermediate Time estimate: 1-2 weeks Prerequisites: C programming, basic understanding of memory addresses
Real world outcome:
- Run your tool on any binary:
./elf-inspect /bin/lsand see a formatted display of all sections, symbols, dependencies, and entry point - Detect whether a binary is stripped, statically linked, or uses specific libraries
- Export findings to JSON for further analysis
Learning milestones:
- Successfully parse and display ELF header fields (magic, architecture, entry point) - you understand binary file structure
- Navigate and display all sections with their permissions and sizes - you understand the static view of binaries
- Extract symbols and show imported/exported functions - you understand how programs reference external code
Project 2: System Call Tracer (strace clone)
- File: REVERSE_ENGINEERING_LINUX_LEARNING_PROJECTS.md
- Main Programming Language: C
- Alternative Programming Languages: Rust, C++, Go
- Coolness Level: Level 4: Hardcore Tech Flex
- Business Potential: 1. The âResume Goldâ (Educational/Personal Brand)
- Difficulty: Level 3: Advanced (The Engineer)
- Knowledge Area: Reverse Engineering, Linux Internals
- Software or Tool: ptrace, Linux syscall interface
- Main Book: âThe Linux Programming Interfaceâ - Michael Kerrisk
What youâll build: A tool that intercepts and logs all system calls made by a running process, showing syscall names, arguments, and return valuesâa minimal strace.
Why it teaches reverse engineering: Dynamic analysis is half of RE. Understanding what a program does at runtime (files opened, network connections made, processes spawned) reveals behavior that static analysis canât. Building this teaches you ptraceâthe same mechanism debuggers use.
Core challenges youâll face:
- Using
ptrace(PTRACE_TRACEME)andPTRACE_SYSCALLto intercept system calls - Reading registers to extract syscall numbers and arguments
- Mapping syscall numbers to names (parsing syscall tables)
- Handling multi-threaded programs and
fork()
Resources for key challenges:
- âPlaying with ptraceâ series by Pradeep Padala - Step-by-step ptrace tutorial
- âThe Linux Programming Interfaceâ Ch. 26 (Process Tracing) - Michael Kerrisk
Key Concepts:
- ptrace API: âThe Linux Programming Interfaceâ Ch. 26 - Michael Kerrisk
- System Calls: âLinux System Programmingâ Ch. 1-2 - Robert Love
- x86-64 Calling Convention: âComputer Systems: A Programmerâs Perspectiveâ Ch. 3 - Bryant & OâHallaron
Difficulty: Intermediate-Advanced Time estimate: 1-2 weeks Prerequisites: C programming, basic Linux syscall knowledge, understanding of processes
Real world outcome:
- Run
./mytrace /bin/cat /etc/passwdand see every syscall:open("/etc/passwd", O_RDONLY) = 3,read(3, "root:x:0:0:...", 4096) = 1823 - Trace a program and discover what files it accesses, what network connections it makes
- Detect suspicious behavior like unexpected file access or network activity
Learning milestones:
- Successfully attach to a process and catch syscall entry/exit - you understand process control
- Decode syscall arguments from registers - you understand calling conventions
- Pretty-print common syscalls with decoded arguments - you can interpret program behavior
Project 3: Interactive Binary Debugger
- File: REVERSE_ENGINEERING_LINUX_LEARNING_PROJECTS.md
- Programming Language: C
- Coolness Level: Level 5: Pure Magic (Super Cool)
- Business Potential: 2. The âMicro-SaaS / Pro Toolâ
- Difficulty: Level 4: Expert
- Knowledge Area: Debugging / Assembly
- Software or Tool: GDB / Ptrace
- Main Book: âThe Art of Debuggingâ by Norman Matloff
What youâll build: A command-line debugger that can set breakpoints, single-step through instructions, inspect registers and memory, and disassemble codeâa minimal GDB.
Why it teaches reverse engineering: Debuggers are the primary RE tool. Building one teaches you exactly how breakpoints work (INT3 injection), how single-stepping uses CPU trap flags, and how to read process memory. Youâll understand what GDB does âunder the hood.â
Core challenges youâll face:
- Injecting
0xCC(INT3) for breakpoints and restoring original bytes - Using
PTRACE_SINGLESTEPand understanding the trap flag - Reading/writing process memory with
PTRACE_PEEKDATA/PTRACE_POKEDATA - Integrating a disassembler library (Capstone) to show instructions
Resources for key challenges:
- âWriting a Linux Debuggerâ by Sy Brand - Complete tutorial series on building a debugger
- âBuilding a Debuggerâ by Sy Brand - No Starch Press book (if available)
Key Concepts:
- Breakpoint Mechanics: âThe Art of Debugging with GDB, DDD, and Eclipseâ Ch. 1-2 - Norman Matloff
- x86 Debug Registers: Intel Software Developer Manual Vol. 3, Ch. 17
- ptrace Deep Dive: âThe Linux Programming Interfaceâ Ch. 26 - Michael Kerrisk
- Disassembly: Capstone Engine documentation
Difficulty: Advanced Time estimate: 2-4 weeks Prerequisites: Completed Project 2, x86-64 assembly basics, comfort with pointers
Real world outcome:
- Debug any program:
./mydbg /bin/ls - Commands like
break main,run,step,regs,mem 0x7fff...,disas - Set a breakpoint, hit it, inspect registers, see disassembled instructions around the current IP
- Single-step through code watching register changes
Learning milestones:
- Set a breakpoint and stop execution when hit - you understand how debuggers intercept execution
- Single-step and display register state - you understand CPU state inspection
- Disassemble and show instructions around current IP - you can follow execution flow
Project 4: Binary Patcher / Crackme Solver
- File: REVERSE_ENGINEERING_LINUX_LEARNING_PROJECTS.md
- Main Programming Language: C
- Alternative Programming Languages: Python, Rust, Assembly
- Coolness Level: Level 4: Hardcore Tech Flex
- Business Potential: 1. The âResume Goldâ (Educational/Personal Brand)
- Difficulty: Level 2: Intermediate (The Developer)
- Knowledge Area: Reverse Engineering, Binary Analysis
- Software or Tool: Ghidra, radare2, objdump
- Main Book: âPractical Binary Analysisâ - Dennis Andriesse
What youâll build: A tool that can analyze simple âcrackmeâ binaries, identify password checks, and patch them to bypass protectionâplus create your own crackmes for others to solve.
Why it teaches reverse engineering: This is applied RE. Youâll combine static analysis (finding the comparison), dynamic analysis (understanding the logic), and patching (modifying the binary). Creating crackmes teaches you to think like a protector.
Core challenges youâll face:
- Identifying comparison instructions (CMP, TEST) and conditional jumps
- Understanding control flow to find the âsuccessâ vs âfailureâ paths
- Patching JNE to JE (or NOPing checks) while maintaining valid ELF structure
- Creating anti-debugging checks for your own crackmes
Key Concepts:
- x86 Control Flow: âPractical Binary Analysisâ Ch. 6 - Dennis Andriesse
- Patching Techniques: âReverse Engineering for Beginnersâ by Dennis Yurichev (free PDF)
- Assembly Patterns: âThe Art of Assembly Languageâ Ch. 7-8 - Randall Hyde
Difficulty: Intermediate Time estimate: 1-2 weeks Prerequisites: Basic x86-64 assembly, ELF understanding from Project 1
Real world outcome:
- Given a crackme binary, use your analysis skills to find and patch the check
- Run
./crackmeâ âAccess Deniedâ â patch â run again â âAccess Granted!â - Create 3 progressively harder crackmes that require: simple string compare patch, multi-condition patch, and anti-debugging bypass
- Share crackmes with friends to solve
Learning milestones:
- Identify the password check in a simple crackme - you can read assembly for meaning
- Patch the binary and bypass the check - you understand binary modification
- Create a crackme with anti-debugging - you understand both sides of RE
Project 5: Library Call Interception Framework
- File: REVERSE_ENGINEERING_LINUX_LEARNING_PROJECTS.md
- Programming Language: C
- Coolness Level: Level 4: Hardcore Tech Flex
- Business Potential: 3. The âService & Supportâ Model
- Difficulty: Level 3: Advanced
- Knowledge Area: Instrumentation / Hooking
- Software or Tool: LD_PRELOAD
- Main Book: âPractical Binary Analysisâ by Dennis Andriesse
What youâll build: A framework using LD_PRELOAD that intercepts library calls (malloc, free, open, connect, SSL_read) to log, modify, or inject behavior into existing programs without source code.
Why it teaches reverse engineering: Understanding how dynamic linking can be exploited is crucial for RE. This technique is used for debugging, instrumentation, and even malware. Youâll learn how the dynamic linker resolves symbols and how to hijack that process.
Core challenges youâll face:
- Creating shared libraries with
RTLD_NEXTto call original functions - Intercepting crypto functions to log plaintext before encryption
- Hooking memory allocators to detect leaks or heap corruption
- Making hooks transparent (timing, side effects)
Key Concepts:
- Dynamic Linking: âThe Linux Programming Interfaceâ Ch. 41-42 - Michael Kerrisk
- LD_PRELOAD Mechanics: âHow to Write Shared Librariesâ by Ulrich Drepper
- GOT/PLT: âPractical Binary Analysisâ Ch. 2 - Dennis Andriesse
Difficulty: Intermediate Time estimate: 1-2 weeks Prerequisites: C programming, shared library basics, understanding of linking
Real world outcome:
- Run
LD_PRELOAD=./malloc_trace.so /bin/lsand see every allocation logged - Intercept
SSL_read/SSL_writeon an HTTPS client to see plaintext data - Build a âuniversal loggerâ that can trace any library call in any program
- Create a âchaos monkeyâ that randomly fails
malloccalls to test program resilience
Learning milestones:
- Intercept
mallocand log allocations - you understand symbol resolution hijacking - Intercept
connect()and log all network connections - you can monitor program behavior - Intercept SSL functions and log decrypted traffic - you understand why runtime analysis is powerful
Project Comparison Table
| Project | Difficulty | Time | Depth of Understanding | Fun Factor |
|---|---|---|---|---|
| ELF Binary Inspector | Intermediate | 1-2 weeks | âââ Binary format fundamentals | âââ Seeing inside binaries |
| System Call Tracer | Intermediate-Advanced | 1-2 weeks | ââââ Process control & syscalls | ââââ Spying on programs |
| Interactive Debugger | Advanced | 2-4 weeks | âââââ Deep ptrace & CPU mechanics | ââââ Building a real tool |
| Binary Patcher/Crackme | Intermediate | 1-2 weeks | âââ Applied analysis & patching | âââââ CTF-style challenges |
| Library Interception | Intermediate | 1-2 weeks | ââââ Dynamic linking internals | ââââ Hijacking programs |
Recommended Learning Path
Based on the scope of reverse engineering, I recommend this progressive path:
-
Start with Project 1 (ELF Inspector) - You need to understand binary format before anything else. This gives you the vocabulary and mental model for everything that follows.
-
Then Project 2 (Syscall Tracer) - Learn ptrace fundamentals and dynamic analysis. This is more immediately useful and builds toward the debugger.
-
Then Project 3 (Debugger) - The capstone project. Once youâve built a debugger, you truly understand how RE tools work.
-
Interleave Project 4 (Crackmes) - Do this alongside or after Project 2-3 as âpracticeâ applying your skills.
-
Project 5 (LD_PRELOAD) - A different angle on instrumentation that complements ptrace-based analysis.
Final Capstone Project: Malware Analysis Sandbox
What youâll build: A complete isolated analysis environment that automatically executes suspicious binaries and produces behavioral reportsâcombining all previous projects into an automated analysis pipeline.
Why it teaches reverse engineering: Real-world RE often means analyzing unknown, potentially malicious code. This project integrates static analysis (ELF parsing), dynamic analysis (syscall tracing), and instrumentation (library hooking) into a cohesive automated system that produces actionable intelligence.
Core challenges youâll face:
- Creating isolated execution environments (containers, VMs, or seccomp sandboxes)
- Combining your ELF inspector for static indicators (strings, imports, sections)
- Using your syscall tracer to capture all runtime behavior
- Detecting anti-analysis techniques (VM detection, timing checks, ptrace detection)
- Generating human-readable reports with behavioral indicators
Resources for key challenges:
- âPractical Malware Analysisâ by Sikorski & Honig - The definitive guide
- Cuckoo Sandbox architecture documentation - How real sandboxes work
Key Concepts:
- Sandbox Design: âPractical Malware Analysisâ Ch. 2-4 - Sikorski & Honig
- Behavioral Analysis: âPractical Malware Analysisâ Ch. 3 - Sikorski & Honig
- Container Isolation: Linux namespaces and seccomp documentation
- Anti-Analysis Detection: âPractical Malware Analysisâ Ch. 16-17 - Sikorski & Honig
Difficulty: Advanced Time estimate: 1 month+ Prerequisites: All previous projects completed, container/VM familiarity
Real world outcome:
- Submit any binary:
./sandbox analyze suspicious_binary - Get a report showing:
- Static indicators: suspicious strings, imports, sections
- Network activity: connections attempted, DNS queries
- File activity: files created, modified, read
- Process activity: children spawned, injections attempted
- Behavioral classification: âThis binary appears to be a reverse shell thatâŚâ
- Web dashboard showing analysis history and threat indicators
- Export IOCs (Indicators of Compromise) in standard formats
Learning milestones:
- Isolated execution that contains any malicious behavior - you understand sandboxing
- Automated static + dynamic analysis with structured output - youâve integrated your tools
- Detection of anti-analysis and evasion attempts - you understand adversarial thinking
- Production-quality reports useful for incident response - youâve built something professionals use
Additional Resources
CTF Platforms for Practice
- pwnable.kr - Binary exploitation challenges
- crackmes.one - Reverse engineering challenges
- picoCTF - Beginner-friendly CTF with RE categories
- Reverse Engineering challenges on HackTheBox
Essential Tools to Master
objdump,readelf,nm- Basic static analysisstrace,ltrace- System/library call tracinggdbwith pwndbg/peda/gef - Enhanced debugging- Ghidra - Free decompiler from NSA
- Radare2/Cutter - Open source RE framework
- Capstone - Disassembly framework for your tools