AFL is really "magical". It finds bugs very quickly and with little effort on our part except to leave it running and look at the results occasionally. We use it to fuzz test a variety of file formats and network interfaces, including QEMU image parsing, nbdkit, libnbd, hivex. We also use clang's libfuzzer with QEMU which is another good fuzzing solution. There's really no excuse for CrowdStrike not to have been using fuzzing.