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When using the make_safe_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 or \\\\\\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.","Type":"Description","Title":null},{"CveYear":"2021","CveId":"23401","Ordinal":"2","NoteData":"2021-07-05","Type":"Other","Title":"Published"},{"CveYear":"2021","CveId":"23401","Ordinal":"3","NoteData":"2021-07-05","Type":"Other","Title":"Modified"}]}}}