The IMGspider plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the 'upload' function in all versions up to, and including, 2.3.10. This makes it possible for authenticated attackers, with contributor-level and above permissions, to upload arbitrary files on the affected site's server which may make remote code execution possible.
https://plugins.trac.wordpress.org/changeset/3107741/imgspider
https://plugins.trac.wordpress.org/browser/imgspider/tags/2.3.10/classes/post.class.php#L189