"We call it a botnet for fuzzing," said Gallagher, referring to what Microsoft has formally dubbed Distributed Fuzzing Framework (DFF). The fuzzing network originated with work by David Conger, a software design engineer on the Access team. Client software installed on systems throughout Microsoft's network automatically kicks in when the PCs are idle, such as on weekends, to run fuzzing tests "We would do millions of [fuzzing] iterations each weekend," Gallagher said -- up to 12 million in some cases.
fonte: http://www.computerworld.com/s/article/9174539/Microsoft_runs_fuzzing_botnet_finds_1_800_Office_bugs
(com agradecimentos ao João Antunes)