WP Meta SEO < 4.4.7 - Admin+ Stored Cross-Site Scripting via breadcrumbs

The plugin does not sanitise or escape the breadcrumb separator before outputting it to the page, allowing a high privilege user such as an administrator to inject arbitrary javascript into the page even when unfiltered html is disallowed.

PoC

As admin, put the following payload in the Breadcrumb separator setting and save: The XSS will be triggered in page/post where Breadcrumb is enabled