This document discusses logical vulnerabilities in web applications. It defines logical vulnerabilities as flaws occurring due to weaknesses in an application's design logic rather than coding errors. The document outlines common logical vulnerability types like payment gateway price manipulation, discount coupon abuse, weak password recovery, negative transfers, and denial of service. It notes that finding logical vulnerabilities is difficult for automated scanners since they often require multi-step exploitation. The document was presented by the CTO of a security firm that performs application penetration testing.