The Masteriyo LMS – LMS Course Builder, Quizzes & Certificates plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 2.2.1. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for authenticated attackers, with student-level access and above, to modify the description (post content) of arbitrary course announcements authored by instructors or administrators.