part of the 7th USENIX Workshop on Offensive Technologies, (Washington, D.C., 2013) available on www.usenix.org 137 “You do not really understand”: Rebecca Shapiro, Sergey Bratus, Sean W. Smith, “Weird Machines’ in ELF: A Spotlight on the Underappreciated Metadata” paper delivered 7th USENIX Workshop on Offensiv