The Top 10 WordPress plugin before 3.2.3 does not validate and escape some of its Block attributes before outputting them back in the page, which could allow users with a role as low as contributor to perform Stored Cross-Site Scripting attacks which could be used against high privilege users such as admins.
https://wpscan.com/vulnerability/a2483ecf-42a6-470a-b965-4e05069d1cef