To compile the file fuzzer you need to have installed on your system the library distorm64. You can download it from http://ragestorm.net/distorm/ Once you installed the .so go to the src directory of ffuzer and issue the following command: gcc PexLike.c file.c fuzzer.c logging.c \ main.c mappings.c parseopts.c parser.c process.c signals.c utils.c x86_disasembly.c \ -I ../include/ -I ../ -lm ../distorm64.a -Wall -o gwar -ggdb -DFUZZ_ALL -DPTRACE Example of use: [gr00vy@kenny ffuzzer]$ ./gwar -i /tmp/input.elf -o /tmp/out.elf -X -D -t 5 -m 4 -r 0-70 "/usr/bin/readelf -a %FILENAME%" That command will give you a lot of fun.