SymFuzz consists of two modules. The first is an input-bit dependence checker, and the second is mutational fuzzer. You can download them from the following link.
$ ./symfuzz -help
For further details, please refer to our paper below. The experimental data may differ from the original copy because we recently fixed a bug in our system after submitting the camera-ready. Program-Adaptive Mutational Fuzzing, Sang Kil Cha, Maverick Woo, and David Brumley, In Proc. of IEEE Security and Privacy, 2015