Affected: thimpress LearnPress – WordPress LMS Plugin for Create and Sell Online Courses

The LearnPress plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 4.4.10 via deserialization of untrusted input from the 'checkout-email' request parameter during the checkout AJAX action. The value is passed through sanitize_text_field(), which does not strip serialized object syntax, then stored in the LearnPress session table and later fed to LP_Helper::maybe_unserialize() → unserialize() (without an allowed_classes restriction) by LP_Session_Handler::get() on subsequent requests. This makes it possible for unauthenticated attackers to inject a PHP Object.