Security Vulnerability

Seems like there is a security issue lately:
https://patchstack.com/database/wordpress/plugin/gutenify/vulnerability/wordpress-gutenify-plugin-1-4-9-cross-site-scripting-xss-vulnerability?_a_id=350

The page I need help with: [log in to see the link]