Demystifying Fuzzer Behaviour

Despite how it's often portrayed in blogs, scientific articles, or corporate test planning, fuzz testing isn't a magic bug printer; just saying "we fuzz our code" says nothing about how _effectively_ it was tested. Yet, how fuzzers and programs interact is deeply mythologised and poorly misunderstood, even by seasoned professionals. This talk analyses a number of recent works and case studies that reveal the relationship between fuzzers, their inputs, and programs to explain _how_ fuzzers work. Fuzz testing (or, "fuzzing") is a testing technique that passes randomly-generated inputs to a subject under test (SUT). This term was first coined in 1988 by Miller to describe sending random byte sequences to Unix utilities (1), but was arguably preceded in 1971 by Breuer for fault detection in sequential circuits (2) and in 1972 by Purdom for parser testing by generating sentences from grammars (3). Curiously, they all exhibit different approaches for generating inputs based on knowledge abo