The amCharts: Charts and Maps plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'amcharts_javascript' parameter in all versions up to, and including, 1.4.4 due to the ability to supply arbitrary JavaScript a lack of nonce validation on the preview functionality. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.
https://plugins.trac.wordpress.org/changeset/3150041/
https://plugins.trac.wordpress.org/browser/amcharts-charts-and-maps/tags/1.4.4/includes/preview.php