reCAPTCHA <= 1.6 - Admin+ Stored XSS

The plugin does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup).

PoC

1. On the setting page of this plugin, enter the following payload in the input boxes. The payload is: 123" onmouseenter=alert(/XSS/) " 2. After saving, refresh the page, and then move the mouse to the input box, it will trigger the XSS.