The Popup Box WordPress plugin before 5.5.0 does not properly validate nonces in the add_or_edit_popupbox() function before saving popup data, allowing unauthenticated attackers to perform Cross-Site Request Forgery attacks. When an authenticated admin visits a malicious page, the attacker can create or modify popups with arbitrary JavaScript that executes in the admin panel and frontend.

The Popup Box WordPress plugin before 5.5.0 does not properly validate nonces in the add_or_edit_popupbox() function before saving popup data, allowing unauthenticated attackers to perform Cross-Site Request Forgery attacks. When an authenticated admin visits a malicious page, the attacker can create or modify popups with arbitrary JavaScript that executes in the admin panel and frontend.