The Happy Addons for Elementor plugin is used for WordPress websites and has a security vulnerability in all versions up until version 3.9.1.1 (and version 2.9.1.1 in Happy Addons for Elementor Pro). This vulnerability means that if attackers can trick a user into performing an action, such as clicking a link, they can inject malicious web scripts into pages. This could be used to cause harm to the website or the user.