The uListing plugin for WordPress is vulnerable to Unauthenticated Arbitrary Account Changes in versions up to, and including, 1.6.6. This is due to missing login checks on the stm_listing_profile_edit AJAX action. This makes it possible for unauthenticated attackers to edit any account on the blog, such as changing the admin account's email address.
https://blog.nintechnet.com/wordpress-ulisting-plugin-fixed-multiple-critical-vulnerabilities/