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    google/syzkaller

    syzkaller is an unsupervised coverage-guided kernel fuzzer

    security
    testing
    fuzz-testing
    fuzzer
    fuzzing
    kernel
    linux
    Go
    Apache-2.0
    6.4K stars
    1.5K forks
    177 GitHub watchers
    Updated Nov 5, 2026
    View on GitHub

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    Where it stands

    Rank, growth pace and release cadence relative to everything GStars tracks.

    The project lists 298 contributors on GitHub.

    Use Cases & Benefits

    • Implements an unsupervised coverage-guided fuzzer for operating system kernels to detect security vulnerabilities and bugs.
    • Supports multiple OS kernels including Linux, FreeBSD, Windows, and others, enabling broad applicability across different environments.
    • Use for automated kernel fuzz testing to discover security flaws and stability issues in Linux kernel development.
    • Use for cross-platform kernel security auditing in environments running FreeBSD, NetBSD, OpenBSD, or Windows kernels.
    • Use for integrating continuous fuzzing in CI pipelines to proactively identify kernel bugs during OS development or maintenance.

    Should you depend on it?

    License terms, project hygiene and risks, from GitHub metadata and GStars' snapshots.

    License

    Apache 2.0

    Permissive: commercial use, modification and redistribution are allowed with attribution; includes an explicit patent grant from contributors.

    Community files

    • README: present
    • Contributing guide: present
    • Code of conduct: present

    Watch-outs

    • No GitHub releases; pin a commit or tag instead of a release.

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    From the README

    syzkaller ([siːzˈkɔːlə]) is an unsupervised coverage-guided kernel fuzzer.
    Supported OSes: FreeBSD, Fuchsia, gVisor, Linux, NetBSD, OpenBSD, Windows.

    Mailing list: [email protected] (join on web or by email).

    Initially, syzkaller was developed with Linux kernel fuzzing in mind, but now it's being extended to support other OS kernels as well. Most of the documentation at this moment is related to the Linux kernel. For other OS kernels check: Darwin/XNU, FreeBSD, Fuchsia, NetBSD, OpenBSD, Starnix, Windows, gVisor. Akaros,

    This is not an official Google product.

    Excerpt from the google/syzkaller README on GitHub (Apache-2.0 license). © its authors.Read the full README on GitHub

    Daily snapshots

    Stars gained per day, and how forks and open issues moved, from GStars' daily snapshots

    Forks

    1.5K+41

    Open issues

    647+33

    Compared with peers in Security

    Fastest-growing repositories GStars tracks in this cohort for the week of Nov 1, by 7-day star growth

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