An issue was discovered in core/assets/form/form_question_types/form_question_type_file_upload/form_question_type_file_upload.inc in Squiz Matrix CMS 5.5.0 prior to 5.5.0.3, 5.5.1 prior to 5.5.1.8, 5.5.2 prior to 5.5.2.4, and 5.5.3 prior to 5.5.3.3 where a user can delete arbitrary files from the server during interaction with the File Upload field type, when a custom form exists. (This is related to an information disclosure issue within the File Upload field type that allows users to view the full path to uploaded files, including the product's web root directory.)