CVE-2025-50817: 
Python vulnerability analysis and mitigation

A critical vulnerability (CVE-2025-50817) has been discovered in Python-Future version 1.0.0, a widely-used module that helps maintain compatibility of legacy code with the latest Python features. The vulnerability was discovered by researchers Yutai Kim, Seungyeon Han, and Changmin Hong from lint.co.kr, and was disclosed in August 2025. The vulnerability allows for arbitrary code execution through the unintended import of a file named test.py when the module is loaded (Medium Blog).

The vulnerability exists in the python-future-master/src/future/standardlibrary/_init.py file at line 491, where test.py is automatically imported and executed when loading the future module. This behavior is similar to DLL Side-Loading attacks. The vulnerability is triggered whenever any import that loads future/standard_library/init_.py is executed. The module automatically imports test.py if present in the same directory or in the sys.path ([Medium Blog](https://medium.com/@abcd68700/cve-2025-50817-python-future-module-arbitrary-code-execution-via-unintended-import-of-test-py-f0818ea93cf4), AttackerKB).

The vulnerability has widespread impact due to python-future's extensive usage, with over 362,000 dependent repositories on GitHub. It affects major enterprise applications including Splunk Enterprise and PyTorch. The vulnerability could lead to Remote Code Execution if a project using the future module provides file upload capabilities or uses shared folders. It can also be used for achieving system persistence and bypassing security controls. The supply chain nature of this vulnerability means systems could be exposed through dependency chains, and enterprise applications may inherit this vulnerability unknowingly (Medium Blog).

As python-future has been confirmed as End-of-Support (EoS) by the maintainers, no security patches will be provided for this vulnerability. Organizations are advised to: 1) Urgently review and audit systems using python-future 1.0.0, 2) Develop a migration strategy away from python-future to alternative solutions, 3) Implement strict controls on file write permissions in directories where python-future is used, 4) Monitor for unexpected test.py files in application directories and sys.path locations, and 5) Consider isolating systems that cannot immediately migrate from python-future (Medium Blog).