VDB
KO
MEDIUM 5.3

GHSA-8vgw-p6qm-5gr7

Flask-CORS allows for inconsistent CORS matching

Details

A vulnerability in corydolphin/flask-cors version 5.0.1 allows for inconsistent CORS matching due to the handling of the '+' character in URL paths. The request.path is passed through the unquote_plus function, which converts the '+' character to a space ' '. This behavior leads to incorrect path normalization, causing potential mismatches in CORS configuration. As a result, endpoints may not be matched correctly to their CORS settings, leading to unexpected CORS policy application. This can cause unauthorized cross-origin access or block valid requests, creating security vulnerabilities and usability issues.

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Affected packages

PyPI / flask-cors
Introduced in: 0 Fixed in: 6.0.0
Fix pip install --upgrade 'flask-cors>=6.0.0'

References