Easy Python Decompiler 100%
# Run original bytecode orig_output = subprocess.check_output(['python', original_pyc])
if orig_output == recov_output: print("✓ Decompilation successful") else: print("✗ Decompilation may have errors") When decompilation produces imperfect code: Easy Python Decompiler
# Original: customer_price = calculate_discount(base_price) # Decompiled: var1 = func1(var2) : Use bytecode analysis with debug info if available. Best Practices 1. Preserve Original Files # Always backup before decompiling cp original.pyc original.pyc.backup uncompyle6 original.pyc > recovered.py 2. Verify Decompilation Quality # Test recovered code import subprocess def test_decompiled(original_pyc, recovered_py): """Compare outputs to verify correctness""" # Run original bytecode orig_output = subprocess
for root, dirs, files in os.walk(input_dir): for file in files: if file.endswith('.pyc'): pyc_path = os.path.join(root, file) rel_path = os.path.relpath(root, input_dir) out_subdir = os.path.join(output_dir, rel_path) os.makedirs(out_subdir, exist_ok=True) py_name = file.replace('.pyc', '.py') output_path = os.path.join(out_subdir, py_name) try: with open(output_path, 'w') as out_file: uncompyle6.decompile_file(pyc_path, out_file) print(f"Success: pyc_path -> output_path") except Exception as e: print(f"Failed: pyc_path - str(e)") batch_decompile("./compiled_files", "./decompiled_source") Handling Different Python Versions # Python 2.7 bytecode uncompyle6 --py-version=2.7 script.pyc Python 3.6 bytecode uncompyle6 --py-version=3.6 script.pyc Python 3.8+ bytecode uncompyle6 --py-version=3.8 script.pyc Decompiling Packaged Executables # Step 1: Extract from .exe (PyInstaller) python pyinstxtractor.py myapp.exe Step 2: Decompile extracted .pyc files uncompyle6 extracted/*.pyc Step 3: Reconstruct package structure Common Issues & Solutions Issue 1: "Unknown magic number" Error # Solution: Identify Python version first file script.pyc # Output: Python 3.8 bytecode Use correct version flag uncompyle6 --py-version=3.8 script.pyc Issue 2: Corrupted or Incomplete Bytecode # Try alternative decompiler import marshal import dis Read raw bytecode with open('script.pyc', 'rb') as f: f.read(16) # Skip header code_obj = marshal.load(f) Display disassembly for analysis dis.dis(code_obj) Issue 3: Missing Variable Names Decompiled code loses original variable names: Verify Decompilation Quality # Test recovered code import
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# Common patterns to fix: # 1. Restore meaningful variable names # 2. Add missing imports # 3. Fix indentation issues # 4. Reconstruct string literals # 5. Restore comments from context # Complete recovery process for lost source code 1. Locate all bytecode files find . -name "*.pyc" > pyc_files.txt 2. Decompile to temporary directory mkdir recovered_source uncompyle6 -o recovered_source $(cat pyc_files.txt) 3. Fix common decompilation artifacts sed -i 's/ doc /"""DOCSTRING"""/g' recovered_source/*.py 4. Validate syntax for file in recovered_source/*.py; do python -m py_compile "$file" done 5. Compare with runtime behavior python -c "import sys; sys.path.insert(0, 'recovered_source'); import your_module" Alternative Tools Comparison | Tool | Python Versions | Speed | Accuracy | Maintenance | |------|----------------|-------|----------|-------------| | uncompyle6 | 1.0-3.8 | Medium | High | Active | | decompyle3 | 3.7-3.9 | Medium | High | Active | | pycdc | 1.0-3.9 | Fast | Medium | Active | | pycdasm | 2.0-3.7 | Slow | Medium | Inactive | | unpyc3 | 3.2-3.6 | Slow | Low | Inactive | Security Considerations Detecting Malicious Code # Scan decompiled code for suspicious patterns suspicious_patterns = [ r'eval\s*\(', r'exec\s*\(', r'__import__\s*\(', r'base64\.b64decode', r'compile\s*\(', r'socket\.', r'subprocess\.' ] def scan_decompiled(filepath): with open(filepath, 'r') as f: content = f.read()
# Most common commands pip install uncompyle6 uncompyle6 file.pyc > recovered.py uncompyle6 -o output/ *.pyc Remember: Decompilation helps recover YOUR lost code, not steal others' work.