The 3 leading WordPress LMS Plugins are: LearnPress, LearnDash, and LifterLMS. These plugins can transform any WordPress website into a fully functioning and easy to use LMS. They are installed on more than 100,000 different educational delivery systems. The problem is that many of the versions are vulnerable. Here's a great research article that details the Application Defects. Warning: its not for the faint of heart.
