Memory corruption vulnerabilities that lead to control-flow hijacking attacks are a common problem for binary executables and such attacks are known for more than two decades. Over the last few years, especially code reuse attacks attracted a lot of attention. In such attacks, an adversary does not need to inject her own code during the exploitation phase, but she reuses existing code fragments (so called gadgets) to build a code chain that performs malicious computations on her behalf. Return-oriented programming (ROP) is a well-known technique that bypasses many existing defenses. Surprisingly, code reuse attacks are also a viable attack vector against web applications.