The Masteriyo LMS WordPress plugin before 3.4.2 does not restrict access to quiz answer keys, allowing any authenticated user, such as a student, to retrieve the correct answers for any quiz on the site, including quizzes in courses they are not enrolled in. The redaction that hides them is applied only to a fixed list of question types, so the answers to every other type are returned in full to anyone able to view the questions.
Analyzing vulnerability vectors…