Best Fuzz Testing Tools for Google OSS-Fuzz

Atheris is a Python fuzzing engine guided by coverage, designed to test both Python code and native extensions developed for CPython. It is built on the foundation of libFuzzer, providing an effective method for identifying additional bugs when fuzzing native code. Atheris is compatible with Linux (both 32- and 64-bit) and Mac OS X, supporting Python versions ranging from 3.6 to 3.10. Featuring an integrated libFuzzer, it is well-suited for fuzzing Python applications, but when targeting native extensions, users may need to compile from source to ensure compatibility between the libFuzzer version in Atheris and their Clang installation. Since Atheris depends on libFuzzer, which is a component of Clang, users of Apple Clang will need to install a different version of LLVM, as the default does not include libFuzzer. The implementation of Atheris as a coverage-guided, mutation-based fuzzer (LibFuzzer) simplifies the setup process by eliminating the need for input grammar definition. However, this approach can complicate the generation of inputs for code that processes intricate data structures. Consequently, while Atheris offers ease of use in many scenarios, it may face challenges when dealing with more complex parsing requirements.

ClusterFuzz is an advanced fuzzing platform designed to identify security vulnerabilities and stability problems within software applications. Utilized by Google for all its products, it also serves as the fuzzing backend for OSS-Fuzz. This infrastructure offers a plethora of features that facilitate the integration of fuzzing into the development lifecycle of software projects. It includes fully automated processes for bug filing, triage, and resolution across different issue trackers. Moreover, it supports various coverage-guided fuzzing engines to achieve optimal outcomes through techniques like ensemble fuzzing and diverse fuzzing strategies. The platform provides detailed statistics for evaluating fuzzer efficiency and tracking crash rates. Its user-friendly web interface simplifies management tasks and crash examinations, while it also accommodates multiple authentication providers via Firebase. Additionally, ClusterFuzz supports black-box fuzzing, minimizes test cases, and employs regression identification through bisection techniques, making it a comprehensive solution for software testing. The versatility and robustness of ClusterFuzz truly enhance the software development process.