- Home
- Fuzz Testing Software
- cargo-fuzz
cargo-fuzz
What it is
cargo-fuzz is a free, open-source Cargo subcommand for fuzzing Rust code. It invokes libFuzzer through the libfuzzer-sys crate rather than acting as a fuzzer itself. To begin, `cargo fuzz init` creates fuzzing files for a crate, and `cargo fuzz add ` creates a target; `cargo fuzz run ` runs it to look for bugs. The tool can minimize a failing input or an input corpus, and version 0.10.0 or newer can generate source-based coverage information. Documentation also covers structure-aware fuzzing using `fuzz_mutator!` and `Arbitrary`, Cargo feature options, and a GitHub Actions workflow for running targets in CI. Supported setups include x86-64 Linux, x86-64 and Apple-Silicon macOS, and Windows with LLVM sanitizer support; Windows programs can also be fuzzed using MSVC AddressSanitizer. It requires the nightly Rust compiler and a C++11-capable compiler. The Rust Fuzz Book names it as its recommended tool for fuzz testing Rust code.
For and against
For
- Creates fuzzing files and targets with Cargo commands
- Minimizes failing inputs and input corpora
- Generates source-based coverage from version 0.10.0
- Supports structure-aware fuzzing and Cargo feature options
- Free and open source under MIT and Apache 2.0
Against
- Requires the nightly Rust compiler
- Requires a C++ compiler with C++11 support
- Coverage requires cargo-fuzz 0.10.0 or newer
The verdict
cargo-fuzz provides a Cargo-based way to run libFuzzer against Rust targets, with input minimization, coverage, and CI guidance. Check its nightly Rust and C++11 build requirements before setting it up.
Who it suits
Rust developers who want to find bugs in code through local fuzzing may find cargo-fuzz useful. Its documented CI workflow and input minimization also suit projects that need repeatable fuzz runs and crash triage.
Plans and prices
cargo-fuzz
MIT license · Apache License (Version 2.0)
Read 2 Oct 2026 · github.com
On the record
- Build requirement
- The setup requires a C++ compiler with C++11 support.rust-fuzz.github.io · read 2 Oct 2026
- CI integration
- The documentation provides a GitHub Actions workflow that installs cargo-fuzz, builds targets, runs them for a configured time, and uploads artifacts on failure.rust-fuzz.github.io · read 1 Oct 2026
- Compiler requirement
- The project requires the nightly Rust compiler because it uses the -Z compiler flag for address sanitization.rust-fuzz.github.io · read 2 Oct 2026
- Configuration
- Fuzz targets can use Cargo feature options including --features, --no-default-features, and --all-features.rust-fuzz.github.io · read 2 Oct 2026
- Corpus minimization
- cargo fuzz tmin minimizes a failing input and cargo fuzz cmin minimizes a corpus of input files.github.com · read 2 Oct 2026
- Coverage
- cargo fuzz coverage generates source-based code coverage information from a fuzz target and corpus.rust-fuzz.github.io · read 2 Oct 2026
- Fuzzer support
- cargo-fuzz is a tool to invoke a fuzzer, and currently supports only libFuzzer through the libfuzzer-sys crate.rust-fuzz.github.io · read 2 Oct 2026
- Fuzz execution
- `cargo fuzz run <target>` runs a fuzzing target to find bugs.github.com · read 1 Oct 2026
- Fuzz targets
- cargo fuzz add creates a new fuzzing target and cargo fuzz run runs a fuzzing target to find bugs.github.com · read 2 Oct 2026
- Input minimization
- The tool provides `cargo fuzz tmin` to minimize a failing input and `cargo fuzz cmin` to minimize a corpus of input files.github.com · read 1 Oct 2026
- Installation
- The documented installation command is cargo install cargo-fuzz.rust-fuzz.github.io · read 2 Oct 2026
- Licensing
- cargo-fuzz is distributed under both the MIT license and Apache License Version 2.0.github.com · read 1 Oct 2026
- Package metadata
- The Cargo package is version 0.13.2 and lists its authors as The rust-fuzz Project Developers.github.com · read 1 Oct 2026
- Project setup
- cargo fuzz init initializes a cargo-fuzz project for a crate.github.com · read 2 Oct 2026
- Purpose
- cargo-fuzz is a cargo subcommand for fuzzing with libFuzzer.github.com · read 2 Oct 2026
- Recommended use
- The Rust Fuzz Book describes cargo-fuzz as the recommended tool for fuzz testing Rust code.rust-fuzz.github.io · read 2 Oct 2026
- Security status
- GitHub reports that the repository has no security policy detected and no published security advisories.github.com · read 2 Oct 2026
- Structured fuzzing
- The documentation supports structure-aware fuzzing through the fuzz_mutator! macro and the Arbitrary trait.rust-fuzz.github.io · read 2 Oct 2026
