GitHub - aflnet/aflnet: AFLNet: A Greybox Fuzzer for Network Protocols (https://thuanpv.github.io/publications/AFLNet_ICST20.pdf)

Fuzzing Network Applications with AFL and libdesock Fuzzing network servers with AFL is challenging since AFL provides its input via stdin or command line arguments while servers get their input over network connections. As the popularity of AFL grew, many attempts have been made of fuzzing popular servers like apache and nginx using different techniques and hacky workarounds. However an off-the-shelf network fuzzing solution for AFL didn’t exist for a long time until so-called “desocketing” tools emerged. These desocketing tools enabled network fuzzing without making a lot of additional modifications to the program under test and quickly became widely used in combination with AFL.

We explain how we built a fuzzer for network applications that we tried to make as efficient and as effective as possible. We utilized custom mutators and input passing over shared memory and found that it gave us a huge speed and coverage boost compared to other network fuzzers.

Marcel Böhme, Max Planck Institute for Security and Privacy