Summary

In this chapter, we learned the changes that the Sloth project makes to qemu-user in order to apply fuzzing to a function in a native library. You have also included into your set of skills another library specific for fuzzing (libFuzzer), and have seem how you can integrate it into qemu-user. There are some major limitations in the Sloth project since, at the moment, it does not yet support the fuzzing of JNI used for the communication between the Java and the native libraries of an Android application. But we agree that the engine behind the ART is very complex, and going through the ART to exploit JNI code would be harder than what has been presented here (it wouldn’t even fit in one chapter of a book). In any case, we think that a project like this opens your mind and teaches you about libFuzzer, an alternative to fuzzers such as AFL or AFL++.

In the next chapter, we will conclude this book with some final remarks and extra acknowledgments.