Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Milan Petrovic GD Mail Queue allows Reflected XSS. This issue affects GD Mail Queue: from n/a through 4.3.

The GD Mail Queue plugin for WordPress is vulnerable to Stored Cross-Site Scripting via email contents in versions up to, and including, 3.9.3 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.