Relevanssi Live Ajax Search <= 2.4 - Unauthenticated WP_Query Argument Injection

The Relevanssi Live Ajax Search plugin for WordPress is vulnerable to argument injection in all versions up to, and including, 2.4. This is due to insufficient validation of input supplied via POST data in the 'search' function. This makes it possible for unauthenticated attackers to inject arbitrary arguments into a WP_Query query and potentially expose sensitive information such as attachments or private posts.