The Welcart e-Commerce WordPress plugin before 2.9.5 does not validate files to be uploaded, as well as does not have authorisation and CSRF in an AJAX action handling such upload. As a result, any authenticated users, such as subscriber could upload arbitrary files, such as PHP on the server
https://wpscan.com/vulnerability/6d29ba12-f14a-4cee-baae-a6049d83bce6