The Weaver Xtreme Theme Support WordPress plugin before 6.3.1 unserialises the content of an imported file, which could lead to PHP object injections issues when a high privilege user import a malicious file and a suitable gadget chain is present on the blog.
https://wpscan.com/vulnerability/421194e1-6c3f-4972-8f3c-de1b9d2bcb13