The Masteriyo LMS – eLearning and Online Course Builder for WordPress plugin for WordPress is vulnerable to unauthorized user profile modification due to missing authorization checks on the /wp-json/masteriyo/v1/users/$id REST API endpoint in all versions up to, and including, 1.13.3. This makes it possible for authenticated attackers, with student-level access and above, to modify the roles of arbitrary users. As a result, attackers can escalate their privileges to the Administrator and demote existing administrators to students.
The Masteriyo LMS – eLearning and Online Course Builder for WordPress plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the question's content parameter in all versions up to, and including, 1.13.3 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with student-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.