CVE-2021-23393 Information

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Reference

https://snyk.io/vuln/SNYK-PYTHON-FLASKUNCHAINED-1293189 https://github.com/briancappello/flask-unchained/commit/71e36b28166f9ffbe0a991f51127f0984f7e6a40 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.

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

REQUIRED

Confidentiality Impact

UNCHANGED

Integrity Impact

LOW

Availability Impact

LOW

Base Score

NONE

Base Severity

5.4