The Meta Box plugin for WordPress is vulnerable to arbitrary file deletion due to insufficient file path validation in the 'ajax_delete_file' function in all versions up to, and including, 5.11.1. This makes it possible for authenticated attackers, with Contributor-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).
https://plugins.trac.wordpress.org/changeset/3475210/meta-box#file3
https://plugins.trac.wordpress.org/browser/meta-box/tags/5.11.0/inc/fields/file.php#L54
https://plugins.trac.wordpress.org/browser/meta-box/tags/5.11.0/inc/fields/file.php#L30