WP User Manager < 2.9.13 - Authenticated (Subscriber+) Arbitrary File Deletion via 'current_user_avatar' Parameter

Description

The WP User Manager plugin for WordPress is vulnerable to Arbitrary File Deletion in all versions up to, and including, 2.9.12. This is due to insufficient validation of user-supplied file paths in the profile update functionality combined with improper handling of array inputs by PHP's filter_input() function. This makes it possible for authenticated attackers, with Subscriber-level access and above, to delete arbitrary files on the server via the 'current_user_avatar' parameter in a two-stage attack which can make remote code execution possible. This only affects sites with the custom avatar setting enabled.