Classified Listing <= 5.3.10 - Missing Authorization to Authenticated (Subscriber+) Arbitrary Modification via add_order_note and send_email_to_user_by_moderator AJAX Actions

The Classified Listing – AI-Powered Classified ads & Business Directory Plugin plugin for WordPress is vulnerable to unauthorized access in all versions up to, and including, 5.3.10. 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 subscriber-level access and above, to add arbitrary notes to any order and trigger unsolicited notification and moderation emails to listing owners without administrative authorization.