wpForo Forum < 3.0.6 - Authenticated (Subscriber+) Arbitrary File Deletion via Custom Profile Field File Path

Description

The wpForo Forum plugin for WordPress is vulnerable to Arbitrary File Deletion in versions up to and including 3.0.5. This is due to two compounding flaws: the Members::update() method does not validate or restrict the value of file-type custom profile fields, allowing authenticated users to store an arbitrary path instead of a legitimate upload path; and the wpforo_fix_upload_dir() sanitization function in ucf_file_delete() only remaps paths that match the expected pattern, and it is passed directly to the unlink() function. This makes it possible for authenticated attackers, with subscriber-level access and above, to delete arbitrary files on the server, which can easily lead to remote code execution when the right file is deleted (such as wp-config.php). Note: The vulnerability requires a file custom field, which requires the wpForo - User Custom Fields addon plugin.