Abuse of Functionality is an attack technique that uses a web site’s own features and functionality to consume, defraud, or circumvents access controls mechanisms. Some functionality of a web site, possibly even security features, may be abused to cause unexpected behavior. When a piece of functionality is open to abuse, an attacker could potentially annoy other users or perhaps defraud the system entirely. The potential and level of abuse will vary from web site to web site and application to application.