FormGent < 1.10.0- Missing Authorization to Unauthenticated Arbitrary File Deletion via 'file_token' Parameter

Description

The FormGent plugin for WordPress is vulnerable to unauthorized arbitrary file deletion due to a missing capability check on the /wp-json/formgent/responses/attachments REST API endpoint in all versions up to, and including, 1.9.2 This is due to the REST API route being registered without any authentication middleware in routes/rest/api.php. This makes it possible for unauthenticated attackers to delete arbitrary files within the formgent uploads directory. Additionally, on Linux servers where the wp-content/uploads/formgent directory does not yet exist (the default state after plugin installation), the path traversal protection can be bypassed, enabling deletion of arbitrary files including wp-config.php which can lead to complete site takeover via a fresh WordPress installation.