Bug bounty programs are put in place so that the security community can help vendors discover tricky and challenging application security flaws. SEC552 is inspired from real-life examples of web and mobile app attacks found in various bug bounty programs. This talk will give an overview on the course and show how it can yield ideas about unconventional attack techniques and mindsets. During the talk, we will focus on tricky logic attack techniques. We will present and demo several attack stories inspired from findings discovered in real life professional experience and bug bounty programs that allow attackers to break defenses.