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libfuzzer

75 / 100 · Review before installing

Check before installing. Some of what it can do is expected: a coding skill usually runs build and test commands.

By trailofbits/skills (GitHub) · coding · 8,130 stars · scanned at commit e4dd0bb

Sets up and runs libFuzzer, the coverage-guided fuzzer built into LLVM, on C/C++ code that compiles with Clang. Covers harness structure, -fsanitize=fuzzer builds, corpus and dictionary management, sanitizer integration, and campaign triage. Use when writing or debugging an LLVMFuzzerTestOneInput harness, starting fuzzing on a C/C++ library, choosing between libFuzzer and AFL++, or working out why a libFuzzer run finds nothing.

Works with any agent that supports SKILL.md skills.

What this skill can do

Safer alternatives

Low-risk skills in the same category (coding) that look related. Check that one does what you need.

• 82 Low risklibfuzzerOutlineDriven/outline-driven-development · 55 stars
• 100 Low riskLibFuzzer Coverage-Guided FuzzingPramodDutta/qaskills · 246 stars

Install

Paste this into your terminal. It downloads exactly the version we scanned, not whatever is newest.

if [ -e ~/.agents/skills/'libfuzzer' ] || [ -L ~/.agents/skills/'libfuzzer' ]; then echo 'A skill folder named libfuzzer already exists — not replacing it' >&2; false; else d=$(mktemp -d) && git clone --quiet --filter=blob:none --no-checkout 'https://github.com/trailofbits/skills' "$d" && git -C "$d" checkout --quiet 'e4dd0bb5b15535f7c5a0834187dffba6ac37e4ff' -- 'plugins/testing-handbook-skills/skills/libfuzzer' && mkdir -p ~/.agents/skills && cp -R "$d"/'plugins/testing-handbook-skills/skills/libfuzzer' ~/.agents/skills/'libfuzzer' && rm -rf "$d"; fi

Codex reads ~/.agents/skills directly. For Claude Code, Cursor, Copilot, Gemini CLI, Antigravity or OpenCode, also link it. For Claude Code: ln -s ~/.agents/skills/'libfuzzer' ~/.claude/skills/'libfuzzer' (other agents: ~/.cursor/skills, ~/.copilot/skills, ~/.gemini/skills, ~/.gemini/config/skills, ~/.config/opencode/skills). Or install through the finder skill, which does both.

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