FuzzDiff

A simple tool designed to help out with crash analysis during fuzz testing. It selectively "un-fuzzes" portions of a fuzzed file that is known to cause a crash, re-launches the targeted application, and sees if it still crashes. Eventually, this will yield a file that still causes the crash, but contains a minimum set of changes from the original un-fuzzed file.

http://vsecurity.com/resources/tool