
PoC and test server
CVE-2026-27641 is a critical security vulnerability affecting versions of the Flask-Reuploaded library. It allows remote attackers to achieve arbitrary file writes
Versions affected: < 1.5.0
To test the vulnerability:
python3 -m venv flask_reuploaded_venv
In flask_reuploaded_venv:
pip install "Flask-Reuploaded==1.4.0"
Start the vuln_server and test the PoC