The Essential Addons for Elementor is a plugin for WordPress that offers various templates, widgets, kits, and builders. However, it has a security vulnerability called Stored Cross-Site Scripting. This means that malicious code can be injected into certain parts of the plugin, specifically the ‘no_more_items_text’ parameter. This can be done by attackers who have Contributor-level access or higher. The injected code can then be executed whenever a user visits the affected page.