Quiz and Survey Master (QSM) < 11.1.5 - Missing Authorization to Authenticated (Contributor+) Arbitrary Modification via qsm_insert_quiz_template AJAX Action

Description

The Quiz and Survey Master (QSM) – Easy Quiz and Survey Maker plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 11.1.4. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for authenticated attackers, with contributor-level access and above, to create, modify, and delete quiz output templates stored in the mlw_quiz_output_templates database table, including storing unsanitized HTML content such as arbitrary script tags.