The directory-pro WordPress plugin before 1.9.5, final-user-wp-frontend-user-profiles WordPress plugin before 1.2.2, producer-retailer WordPress plugin through TODO, photographer-directory WordPress plugin before 1.0.9, real-estate-pro WordPress plugin before 1.7.1, institutions-directory WordPress plugin before 1.3.1, lawyer-directory WordPress plugin before 1.2.9, doctor-listing WordPress plugin before 1.3.6, Hotel Listing WordPress plugin before 1.3.7, fitness-trainer WordPress plugin before 1.4.1, wp-membership WordPress plugin before 1.5.7, sold by the same developer (e-plugins), do not implementing any security measures in some AJAX calls. For example in the file plugin.php, the function iv_directories_update_profile_setting() uses update_user_meta with any data provided by the ajax call, which can be used to give the logged in user admin capabilities. Since the plugins allow user registration via a custom form (even if the blog does not allow users to register) it makes any site using it vulnerable.
https://wpscan.com/vulnerability/d079cb16-ead5-4bc8-b0b8-4a4dc2a54c96