The Sensei LMS WordPress plugin before 4.26.4 contains a broken access control vulnerability in the legacy savenewmessage handler hooked on the init action, which validates only a generic nonce without verifying course enrollment or restricting postid to valid post types. Authenticated attackers, including unprivileged Subscribers, can supply an arbitrary postid for any course, lesson, or quiz to create a private message addressed to that post's author, bypassing the enrollment checks enforced by the newer REST send-message controller.

The Sensei LMS WordPress plugin before 4.26.4 contains a broken access control vulnerability in the addnewmoduleterm AJAX handler that allows authenticated Teacher-role attackers to assign module taxonomy terms to arbitrary courses by supplying a crafted courseid, since the handler validates only a generic nonce and checks manageoptions solely for slug prefixing rather than verifying course edit permissions. Attackers can reuse a nonce obtained from their own course metabox to call wpsetobjectterms against courses owned by other teachers or administrators, enabling unauthorized modification of course content they do not own.