GHSA-9w2p-rh8c-v9g5
Local Privilege Escalation in Windows
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| PyPI | pyinstaller | < 5.13.1 | 5.13.1 |
Details
As written in the advisory (Markdown source, shown as plain text).
### 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](https://github.com/python/cpython/blob/0fb18b02c8ad56299d6a2910be0bab8ad601ef24/Lib/shutil.py#L623) 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.
References
External links from the advisory. They lead to third-party sites.
- https://github.com/pyinstaller/pyinstaller/security/advisories/GHSA-9w2p-rh8c-v9g5
- https://nvd.nist.gov/vuln/detail/CVE-2023-49797
- https://github.com/pyinstaller/pyinstaller/pull/7827
- https://github.com/pyinstaller/pyinstaller
- https://github.com/pypa/advisory-database/tree/main/vulns/pyinstaller/PYSEC-2023-292.yaml
- https://github.com/python/cpython/blob/0fb18b02c8ad56299d6a2910be0bab8ad601ef24/Lib/shutil.py#L623
- https://lists.fedoraproject.org/archives/list/[email protected]/message/2K2XIQLEMZIKUQUOWNDYWTEWYQTKMAN7
- https://lists.fedoraproject.org/archives/list/[email protected]/message/ISRWT34FAF23PUOLVZ7RVWBZMWPDR5U7