The Quiz and Survey Master (QSM) WordPress plugin before 9.0.2 does not validate and escape some of its Quiz fields before outputting them back in a page/post where the Quiz is embed, which could allow users with the contributor role and above to perform Stored Cross-Site Scripting attacks
https://wpscan.com/vulnerability/a2270ee1-3211-4b16-b3d7-6cdd732f7155/