The WP Popup Magic plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'name' parameter of the [wppum_end] shortcode in all versions up to, and including, 1.0.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
https://plugins.trac.wordpress.org/browser/wppopupmagic/trunk/class-wppum-frontend.php#L622
https://plugins.trac.wordpress.org/browser/wppopupmagic/tags/1.0.0/class-wppum-frontend.php#L622