offensive-fuzzing-course

offensive-fuzzing-course is a skill for Claude Code, Codex from SnailSploit/Claude-Red. It costs 0 tokens per session (22,254 once invoked), scanned C, original, MIT.

A guided course section on finding software bugs by feeding programs many generated or altered inputs. It covers choosing targets, building test inputs, using AFL++ or libFuzzer, and sorting the crashes that result.

In plain words
What is it for?
Use it to set up fuzzing campaigns, choose a testing harness, generate input collections, and review or group fuzzer crashes.
Why use it?
It gives a structured way to plan fuzzing instead of relying on random tests. It also helps separate duplicate crashes from distinct problems.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: positional $N argument.

Not installable: its command points at a path on the author’s own machine, so it runs nowhere else. The line is /home/USER/soft/syzkaller/workdir.

Good fit Use it to set up fuzzing campaigns, choose a testing harness, generate input collections, and review or group fuzzer crashes.

Compare 6 skills from other repositories ↓
About the project

claude-red is a library of structured skills that give Claude specialized offensive-security methods for areas such as web vulnerabilities, shellcode, exploit development, and identity systems. It is intended for authorized red-team work, bug-bounty triage, security research, CTF preparation, and operator training. Its catalogue contains the project's skills for loading these security specializations into Claude.

SnailSploit/Claude-Red · 3,040 stars · on GitHub

Install

Getting it into your agent

There is no command for this one: it runs only inside a plugin, and the catalogue could not identify which plugin ships it. The source is linked below.

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for offensive-fuzzing-course

README.md
[![agentmods](https://agentmods.dev/badge/skills/snailsploit/claude-red/offensive-fuzzing-course.svg)](https://agentmods.dev/skills/snailsploit/claude-red/offensive-fuzzing-course)
Your own site
<a href="https://agentmods.dev/skills/snailsploit/claude-red/offensive-fuzzing-course"><img src="https://agentmods.dev/badge/skills/snailsploit/claude-red/offensive-fuzzing-course.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 22,254 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 4 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00000 $0.22254
Opus 5 $0.00000 $0.11127
Sonnet 5 $0.00000 $0.04451
Haiku 4.5 $0.00000 $0.02225

Measured 8d ago against content hash 1094410fb2a8, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade C, and why

offensive-fuzzing-course scanned grade C with 4 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Asks for rootlowPrivilege escalation

A mod that escalates privileges can change anything on the machine, not only the project.

sudo apt update

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Downloads and executes remote codemediumSupply chain

curl | sh runs whatever the server returns today, which is not necessarily what it returned when this was reviewed.

curl --proto '=https' --tlsv1.2 -sSf "https://sh.rustup.rs" | sh

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Unrestricted tool accesslowExcessive agency

A wildcard tool grant or "run any command" leaves no least-privilege boundary at all.

- Execute arbitrary code

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

ninja-build cmake git wget python3.12-venv meson
Skills/fuzzing/offensive-fuzzing-course/SKILL.md · 2,104 lines

How it starts

The opening of the file, as written. The whole thing — 2,104 lines — stays where its author put it; the contents beside it link to each section on GitHub.

SKILL: Week 2: Finding Vulnerabilities Through Fuzzing

Metadata

Description

Week 2 of the exploit development curriculum. Covers fuzzing methodology: target selection, corpus generation, coverage-guided fuzzing with AFL++/libFuzzer, structured fuzzing, and triage/deduplication. Use when setting up fuzz campaigns, selecting harness strategies, or triaging fuzzer output.

Trigger Phrases

Use this skill when the conversation involves any of: fuzzing curriculum, AFL++, libFuzzer, coverage-guided fuzzing, corpus generation, harness, fuzz target, mutation, triage, crash dedup, week 2, exploit dev course

Instructions for Claude

When this skill is active:

  1. Load and apply the full methodology below as your operational checklist
  2. Follow steps in order unless the user specifies otherwise
  3. For each technique, consider applicability to the current target/context
  4. Track which checklist items have been completed
  5. Suggest next steps based on findings

Full Methodology

Week 2: Finding Vulnerabilities Through Fuzzing

Overview

created by AnotherOne from @Pwn3rzs Telegram channel.

This document is Week 2 of a multi‑week exploit development course, focusing on discovering vulnerabilities through fuzzing techniques and analyzing the crashes to determine exploitability.

Last week we studied vulnerability classes through real-world examples. This week we'll learn to find these vulnerabilities ourselves using fuzzing - the automated technique that has discovered thousands of critical security bugs in production software.

Fuzzing can feel a bit front‑loaded: you may spend time wiring harnesses and running campaigns without immediately finding exciting new bugs, especially on hardened or well‑tested targets. That’s normal, and it's one reason the next week on patch diffing often feels more directly "practical" — many companies already run large fuzzing setups and need people who can understand and exploit the bugs those systems uncover. Still, working through this week is important: it teaches you how fuzzers actually discover real vulnerabilities, so when you later triage crashes or study patches, you'll have a solid intuition for how those bugs were found and how to reproduce them.

Read the full file on GitHub · 2,104 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 8d ago First seen · 2,104 lines · 0 tokens per session scan C 1094410fb2a8

Subscribe to this mod's changes

offensive-fuzzing-course is a skill published in the GitHub repository SnailSploit/Claude-Red (3,040 stars, last pushed 8d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 22,254 tokens. A static security scan graded it C with 4 findings (asks for root, downloads and executes remote code, unrestricted tool access). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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