MimicShield 🛡️

Advanced Polymorphic Python Script Protector, Bytecode Obfuscator & Execution Shield

MimicShield (mimic-shield) is a multi-layered Python script protection framework developed as a collaborative 4-person engineering project. Unlike standard packers that simply base64-encode strings, MimicShield compiles your Python source into compiled AST bytecode, compresses it through dual-stage LZMA/zlib algorithms, seals it with an HMAC-SHA256 integrity checksum, and executes directly in memory using a rolling XOR polymorphic loader.

👥 4-Person Architecture & Contribution Matrix

This project is cleanly modularized into 4 independent sub-systems, each handled by one dedicated team member:

🔒 Why Reverse Engineering & AI Analysis Fail

Traditional obfuscators fail because they pass plain strings to exec(), which anyone can intercept with print(). MimicShield uses multi-barrier defenses:

1. No Plaintext Source in Output: The original code is compiled into raw Python bytecode and serialized with marshal. Static deobfuscators and LLMs see only base85 ciphertext.
2. Anti-Stepping & Breakpoint Defense: If an analyst sets breakpoints in an IDE or runs step-through debuggers, high-precision delta counters detect the execution latency and terminate immediately.
3. Anti-Tampering HMAC Seal: Modifying even a single character in the payload or attempting to replace variables invalidates the HMAC-SHA256 signature, immediately aborting execution.
4. Opaque Predicates to Confuse AI Analyzers: Dynamic junk branches and mathematical noise prevent AI reasoning engines and static CFG (Control Flow Graph) builders from tracing execution flow.
5. Anti-Rollback Time Lock: The expiration mechanism queries external authoritative HTTP/NTP date headers to verify timestamps even if an attacker alters their local system clock.

🚀 Installation

Install via pip:

pip install mimic-shield

Or install locally in editable development mode:

git clone https://github.com/mimicpy/mimicpy.git
cd mimicpy
pip install -e .

💻 Usage

1. Interactive CLI Mode

Simply run the command:

mimic
# or
mimicpy

Follow the prompts:

1. Enter the target script filename (e.g. main.py).
2. Select protection preset:
   • Preset 1: High Protection (Anti-Debug + Timing Check + No Expiration).
   • Preset 2: Timed License (High Protection + Set Hard Expiry Date & Time).
   • Preset 3: Custom Protections.

Output is generated as mimic_<script_name>.py.

2. Command Line Automation Mode

For headless builds and automated scripting:

# Basic high-protection armor
mimic -i bot.py -o protected_bot.py

# With network-verified hard expiration
mimic -i bot.py -o protected_bot.py -e "2026-12-31 23:59"

# Without anti-debugging check (e.g. for development testing)
mimic -i bot.py -o protected_bot.py --no-anti-debug

🏗️ Architecture Flow

[Raw Python Script]
       │
       ▼ [Member 1: encoder.py]
  AST Compile ──► Marshal Bytes ──► Dual Compress (LZMA+Zlib) ──► Rolling XOR
       │
       ▼ [Member 2: verifier.py]
  HMAC-SHA256 Seal + Anti-Debug + Timing Probe + Network Expiry Logic
       │
       ▼ [Member 3: generator.py]
  Opaque Predicate Injection + Polymorphic Identifiers + Direct Memory Loader
       │
       ▼ [Member 4: cli.py]
  Assembled Executable: mimic_<script>.py (Direct RAM Execution via marshal.loads)

📜 License

Distributed under the MIT License. See LICENSE for more information.