Chained Quiz <= 1.3.2.4 - Cross-Site Request Forgery to Question Deletion

The Chained Quiz plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 1.3.2.4. This is due to missing nonce validation on the list_questions() function. This makes it possible for unauthenticated attackers to delete questions from quizzes via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.