cve/2021/CVE-2021-23393.md

CVE-2021-23393

Description

This affects the package Flask-Unchained before 0.9.0. When using the the _validate_redirect_url function, it is possible to bypass URL validation and redirect a user to an arbitrary URL by providing multiple back slashes such as \\evil.com/path. This vulnerability is only exploitable if an alternative WSGI server other than Werkzeug is used, or the default behaviour of Werkzeug is modified using 'autocorrect_location_header=False.

POC

Reference

• https://snyk.io/vuln/SNYK-PYTHON-FLASKUNCHAINED-1293189

Github

No PoCs found on GitHub currently.