GHSA-9w2p-rh8c-v9g5 Local Privilege Escalation in Windows

• PyPI pyinstaller: < 5.13.1 → fixed in 5.13.1

Impact A PyInstaller built application, elevated as a privileged process, may be tricked by an unprivileged attacker into deleting files the unprivileged user does not otherwise have access to. A user is affected if all the following are satisfied: • The user runs an application containing either `matplotlib` or `win32com`. • The application is ran as administrator (or at least a user with higher privileges than the attacker). • The user's temporary directory is not locked to that specific user (most likely due to `TMP`/`TEMP` environment variables pointing to an unprotected, arbitrary, non default location). • Either: • The attacker is able to very carefully time the replacement of a temporary file with a symlink. This switch must occur exactly between `shutil.rmtree()`'s builtin symlink check and the deletion itself • The application was built with Python 3.7.x or earlier which has no protection against Directory Junctions links Patches The vulnerability has been addressed in https://github.com/pyinstaller/pyinstaller/pull/7827 which corresponds to `pyinstaller >= 5.13.1` Workarounds _Is there a way for users to fix or remediate the vulnerability without upgrading?_ No workaround, although the attack complexity becomes much higher if the application is built with Python >= 3.8.0.