How I Hacked Google App Engine: Anatomy of a Java Bytecode Exploit

Back in college, I was very interested in Java bytecode. When I got an internship at Google in 2013, I was skeptical of the security of the Java version of Google App Engine and got permission to spend the last week of my internship doing a mini red team exercise, trying to break into App Engine. This is the story of how I found a vulnerability and developed an exploit to break out of the App Engi