The Yuzo Related Posts plugin, which is installed on over 60,000 websites, was removed from the WordPress.org plugin directory on March 30, 2019 after an unpatched vulnerability was publicly, and irresponsibly, disclosed by a security researcher that same day. The vulnerability, which allows stored cross-site scripting (XSS), is now being exploited in the wild. These attacks appear to be linked to the same threat actor who targeted the recent Social Warfare and Easy WP SMTP vulnerabilities.

https://www.wordfence.com/blog/2019/04/yuzo-related-posts-zero-day-vulnerability-exploited-in-the-wild/