WordPress Pie Register plugin before 3.7.0.1 is susceptible to cross-site scripting. The plugin does not sanitize the invitaion_code GET parameter when outputting it in the Activation Code page. An attacker can inject arbitrary script in the browser of an unsuspecting user in the context of the affected site, which can allow the attacker to steal cookie-based authentication credentials and launch other attacks.
Successful exploitation of this vulnerability could lead to the execution of arbitrary script code in the context of the victim's browser, potentially allowing an attacker to steal sensitive information or perform actions on behalf of the victim.
