CVE-2026-93779: Tutor LMS <= 4.1.2 - Insecure Direct Object Reference to Authenticated (Subscriber+) Sensitive Information Exposure via REST API Endpoints

The Tutor LMS – eLearning and online course solution plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 4.1.2 via the initroutes due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with subscriber-level access and above, to read paid course lesson and topic content without enrollment, retrieve quiz answer keys including the iscorrect field before attempting a quiz, and enumerate the email addresses, usernames, and registration data of other users including instructors and administrators. Exploitation requires that the attacker hold a valid Tutor LMS API key/secret pair, which is issued to subscriber-level users through the plugin's API key management feature.