ossfuzz
Free distributed continuous fuzzing infrastructure for open-source projects with integrated coverage and bug tracking.
- Provides CLI helper script for building Docker images, compiling fuzzers with sanitizers (AddressSanitizer, UndefinedBehaviorSanitizer), and running harnesses locally
- Supports multiple fuzzing engines (libFuzzer, AFL++) and languages (C/C++, Python via Atheris, Rust, Go) with language-specific base images
- Includes public bug tracker, build status dashboard, and Fuzz Introspector for coverage analysis and performance bottleneck identification
- Projects must meet criticality score threshold for public enrollment, but core is open-source for hosting private instances
OSS-Fuzz
OSS-Fuzz is an open-source project developed by Google that provides free distributed infrastructure for continuous fuzz testing. It streamlines the fuzzing process and facilitates simpler modifications. While only select projects are accepted into OSS-Fuzz, the project's core is open-source, allowing anyone to host their own instance for private projects.
Overview
OSS-Fuzz provides a simple CLI framework for building and starting harnesses or calculating their coverage. Additionally, OSS-Fuzz can be used as a service that hosts static web pages generated from fuzzing outputs such as coverage information.
Key Concepts
| Concept | Description |
|---|---|
| helper.py | CLI script for building images, building fuzzers, and running harnesses locally |
| Base Images | Hierarchical Docker images providing build dependencies and compilers |
| project.yaml | Configuration file defining project metadata for OSS-Fuzz enrollment |
| Dockerfile | Project-specific image with build dependencies |
| build.sh | Script that builds fuzzing harnesses for your project |
| Criticality Score | Metric used by OSS-Fuzz team to evaluate project acceptance |
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