June 2, 2026

# I Built 30 Claude Code Skills for Bug Bounty Hunters — Here’s Why You Need Them in Your Claude

## How structured Skills turn Claude Code from a chatbot into an end-to-end hunting partner — and why every HackerOne / Bugcrowd hunter…

ghostcat

8 min read

## How structured Skills turn Claude Code from a chatbot into an end-to-end hunting partner — and why every HackerOne / Bugcrowd hunter should install them today.

## The 3 AM realization

Three weeks ago, I was hunting an H1 program at 3 AM. I'd just found what looked like an IDOR. I asked Claude:

"I found IDOR on this endpoint. Help me write a HackerOne report."

Claude wrote a generic report. It was fine. Technically correct. Triage downgraded it to Informative within 24 hours.

The next week, I tried again. Same finding pattern on a different program. This time I'd prepared — I'd loaded a set of structured Claude Code Skills I'd built around the actual HackerOne workflow. I asked:

"I found IDOR on this endpoint. Run the 7-Question Gate, then draft the H1 report."

Claude pulled up a validation framework, asked me 7 specific questions about scope, impact, duplicates. Three of my answers exposed weaknesses I'd missed. I fixed two of them in 20 minutes. The third revealed a chain to full Account Takeover I hadn't considered.

The bounty paid $750.

That's when I knew the methodology gap was costing me money.

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## Why vanilla Claude isn't enough for bug bounty

Claude is brilliant at general security knowledge. But bug bounty is a specific workflow on specific platforms with specific quirks:

  • HackerOne uses CVSS 3.1 with CWE structured fields

  • Bugcrowd uses VRT (Vulnerability Rating Taxonomy, P1-P5)

  • Each program has unique scope, OOS lists, and excluded vuln classes

  • Validation matters — N/A reports tank your signal score, blocking private invites

  • Chains matter — open redirect alone = N/A; open redirect + OAuth callback = Critical ATO

  • Recon at scale requires 30+ specific tools chained together

  • Reports have platform-specific formats and bounty tables

A generic AI assistant doesn't know any of this. So you spend hours teaching it the context for every single task. Or worse — you skip the context, your report gets downgraded, and your reputation suffers.

— -

## What Claude Code Skills are

Claude Code (Anthropic's CLI) supports a feature called Skills — markdown files Claude auto-loads when you describe a relevant task. They're triggered by natural language: you don't invoke them, they invoke themselves when your message matches their trigger phrases.

A Skill contains:

  • YAML frontmatter (name, description, when to invoke)

  • Methodology section

  • Tool commands (copy-paste ready)

  • Payload arsenals

  • Output templates

  • Cross-references to other Skills

Once installed in ~/.claude/skills/, every Claude Code session has access to them. You don't paste anything in. You just describe what you need, and the relevant Skill activates.

This is the killer feature for bug bounty: instead of explaining the methodology each time, you describe the task and Claude already knows the workflow.

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## The arsenal: Claude CyberSecurity Skills

I packaged 30 production-grade Skills for bug bounty hunters into a project called Claude CyberSecurity Skills.

### The 5-phase workflow


Phase 1: PRE-HUNT (3 skills)

└── Pick program → Parse scope → Mind map app

Phase 2: RECON (6 skills)

└── Subdomain → Assets → Tech → JS → Fuzz → Monitor

Phase 3: HUNT (15 skills)

└── IDOR, XSS, SQLi, SSRF, JWT, OAuth, GraphQL,

SSTI, File Upload, Auth Bypass, ATO Chains,

Business Logic, Subdomain Takeover,

Cache Poisoning, HTTP Smuggling

Phase 4: FRONTIER (3 skills)

└── LLM/AI security, Mobile (Android), Cloud

Phase 5: OUTPUT (3 skills)

└── Triage Validation → H1 Report → BC Report

### What's inside

  • 30 Skills — each with methodology, tool commands, payloads, output templates

  • 60+ real tools integrated — subfinder, nuclei, sqlmap, ffuf, dalfox, jwt_tool, SSRFmap, MobSF, semgrep, and more

  • 5 end-to-end playbooks — multi-skill chains for common scenarios

  • 17 arsenal resources — XSS polyglots, CSP bypass cheatsheets, SSRF IP bypass guide, SSTI multi-engine payloads, custom sqlmap tampers, custom nuclei templates, semgrep secret detection rules

  • 5 report templates — HackerOne, Bugcrowd, Intigriti, Immunefi (Web3), CVSS quick calculator

  • 5 automation scripts — continuous monitoring via cron + GitHub Actions

77 files. MIT licensed. Free.

— -

## Workflow comparison: before vs after

### Before (vanilla Claude):


YOU: "I got invited to an H1 program at example.com. Help me start."

CLAUDE: "Sure! Here are some general tips: read the scope, look for

common vulnerabilities…"

YOU: "OK now subdomain enumeration."

CLAUDE: "You can use subfinder, amass, or assetfinder…"

YOU: "Give me the exact commands with API key configuration."

CLAUDE: [generic example commands]

YOU: "What should I test for on the live hosts?"

CLAUDE: "Common things include XSS, SQL injection…"

[3 hours later]

YOU: "I found an IDOR. Write the H1 report."

CLAUDE: [generic report format, no validation framework]

### After (with Claude CyberSecurity Skills):


YOU: "I got invited to an H1 program at example.com. Help me hunt."

[Claude auto-loads: program-selection, scope-analysis, threat-modeling-mindmap]

CLAUDE: "Program scored 28/35 across 7 criteria. Recommended hunt focus:

the GraphQL API at api.example.com. Here's the parsed scope,

the OOS filter, and the prioritized threat model.

Ready to start recon?"

YOU: "Yes."

[Claude auto-loads: subdomain-enum, asset-discovery, fingerprinting,

js-analysis, content-discovery]

CLAUDE: [executes the chained pipeline, outputs structured loot directory]

YOU: "The JS analysis revealed a GraphQL endpoint with introspection

enabled. Hunt IDORs."

[Claude auto-loads: graphql, idor-hunting]

CLAUDE: "Here's the methodology for GraphQL field-level IDOR (BOLA).

I'll pull the schema first, then we'll iterate through every

Query.*ById field with your victim account's IDs…"

YOU: "Found one. Validate it before I report."

[Claude auto-loads: triage-validation]

CLAUDE: "Let's run the 7-Question Gate:

1. Is this in scope?

2. Is the vuln class accepted?

3. Do I have a working PoC?

…"

YOU: "All 7 pass. Write the H1 report."

[Claude auto-loads: hackerone-reporting]

CLAUDE: [full structured report drafted with CVSS 3.1 vector,

CWE, impact framing, suggested fix, and proper

attachment list — ready to submit]

The second flow takes 2–3 hours instead of 8. The report quality is dramatically higher. And every component is explainable to triage.

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## The hidden gem: validation gates

The single most underrated bug bounty skill is knowing what NOT to submit.

A high N/A ratio kills your signal score. Your signal score drops, your private invites dry up, your future bounty potential collapses.

The arsenal includes a triage-validation skill with three components:

### 1. The 7-Question Gate

Every finding must pass:

  1. Is this in scope?

  2. Is the vuln class accepted by this program?

  3. Do I have a working PoC?

  4. What is the real-world impact?

  5. Is this a duplicate?

  6. What severity will the program assign?

  7. Does it pass the "would I pay for this" test?

One "No" → kill the finding or improve it.

### 2. The Always-Rejected List

40+ documented patterns that programs reject:

  • Self-XSS only

  • Missing security headers (no exploit)

  • CSRF on logout

  • Subdomain takeover (if excluded)

  • Email enumeration via login error

  • And many more

If you ship one of these, you lose signal score for nothing.

### 3. The Conditional Chain Table

40+ combinations where weak findings become Critical:

| Weak finding | + Condition | = Combined severity |

| — -| — -| — -|

| Open redirect | + OAuth callback abuse | Critical ATO |

| IDOR (read email) | + email-only password reset | Critical mass ATO |

| SSRF to localhost | + cloud metadata reachable | Critical IAM |

| XSS (popup) | + cookie not HttpOnly | Session theft |

| File upload (SVG) | + admin views profile | Admin ATO |

| Cache unkeyed input | + reflected XSS | Mass XSS |

Once you internalize the chains, your "low-severity" findings become Critical findings — same effort, 10x payout.

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## Continuous monitoring: the passive income play

Here's what nobody tells you: most bounties are time-sensitive.

A new subdomain appears. A new JS file changes. A new tech stack ships. The first hunter to test it wins.

The arsenal ships a complete continuous monitoring system:

  • Nightly subdomain enumeration with diff alerts

  • Real-time Certificate Transparency monitoring (CertStream)

  • JS file hash + endpoint diff every 6 hours

  • Daily nuclei sweep for Critical/High findings

  • Notifications via Discord / Slack / Telegram

Two deployment paths:

  • VPS ($5–10/month) — full control via cron + systemd

  • GitHub Actions (free, 2000 minutes/month) — no infrastructure

I wake up to Discord messages like:

🆕 New subdomain for target.com:

admin-staging.target.com [200] Tech: Spring Boot 2.5.4

I check it. /actuator/env exposed. Critical report by 10 AM. $5k paid by EOD.

This is the difference between hunting and being a hunter.

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## The ROI numbers

For a hunter spending 10 hours/week:

| Metric | Vanilla Claude | With Skills | Change |

| — -| — -| — -| — -|

| Initial recon per target | 4–8 hours | 30 min | 87% less |

| Time per finding (end-to-end) | 7–16 hours | 2–4 hours | 75% less |

| Findings per month | 1–2 | 4–8 | 4x more |

| Report rejection rate | ~30–40% | ~5–15% | 4x better |

Annual estimate at $1,000 average bounty:

  • Without: $12k-24k

  • With: $48k-96k

These are estimates. Individual results vary based on skill, target choice, and market timing. But the productivity gap is real, measurable, and consistent across the hunters I've shared this with.

The cost? $0 for the arsenal, $5–10/month for a small VPS if you want continuous monitoring. Many hunters can run entirely free via GitHub Actions.

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## Install in 5 minutes


# Linux / WSL (recommended)

git clone [https://github.com/](https://github.com/0xGhostCAT/claude-ai-cyber-security-skills)0xGhostCAT[/claude-cybersecurity-skills](https://github.com/0xGhostCAT/claude-ai-cyber-security-skills)

cd claude-cybersecurity-skills

chmod +x INSTALL.sh

./INSTALL.sh

# Installs 60+ tools, configures everything,

# and installs Skills to ~/.claude/skills/

Then from any directory:


claude "hunt this H1 program at example.com"

Claude takes it from there. The Skills auto-load. You become the navigator, not the operator.

For Windows: INSTALL.ps1 handles native install. For containerized: docker build -f docker/claude-cybersecurity-skills.Dockerfile .

— -

## What you actually get

Let me be concrete about the value:

✅ No more Googling payloads mid-hunt — they're already in context.

✅ No more wondering about scope rules — the validation gate enforces it.

✅ No more report rewrites — the templates are platform-specific.

✅ No more missed vuln classes — the methodology covers all 15.

✅ No more starting from scratch on new targets — the workflow is encoded.

✅ No more losing first-finder advantage — monitoring catches new attack surface for you.

✅ No more guessing severity — CVSS reference + VRT table are one query away.

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## Roadmap

This is v1.0. I'm shipping:

  • v1.1: iOS recon, Smart contract (Solidity) skills, additional nuclei templates

  • v1.2: MCP servers for direct Burp / Semgrep integration, Skill evaluation framework

  • v2.0: Multi-agent workflows, knowledge graph across engagements

Community contributions welcome. See CONTRIBUTING.md in the repo.

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## The bigger picture

Bug bounty is a compound skill. Every hour you spend on methodology pays back for years. Every payload you learn applies to the next target. Every chain you discover unlocks new bug classes.

The arsenal accelerates the compounding. It doesn't replace the work — there's no shortcut to becoming a great hunter. But it removes the friction that kills momentum:

  • Forgetting a payload variant you knew six months ago

  • Missing a vuln class you didn't have time to test

  • Fumbling a report under pressure at 2 AM

  • Skipping validation and tanking your N/A ratio

  • Losing first-finder advantage because you scan monthly instead of nightly

If you've been hunting for months without finding consistent bounties, the gap is probably methodology, not skill. Most hunters know the bugs. Few have a complete workflow.

This arsenal closes that gap.

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## Final word

If Claude Code is sitting on your machine and you're hunting bugs, you're leaving money on the table by using it generically. Skills are a force multiplier specifically because they encode workflow.

You don't need to use mine. You can build your own. But you should use something structured.

The arsenal is free, MIT licensed, and production-ready.

🔗 github.com/0xGhostCAT/claude-cybersecurity-skills

If you find it useful:

  • ⭐ Star the repo

  • 🔁 Share with hunters who'd benefit

  • 💬 Open issues / discussions for new skills you want

  • 🤝 Contribute back

The community wins when knowledge compounds.

Hunt ethically. Get paid. Help secure the web.

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If this article was useful, I'd appreciate a clap (or 50 👏). It helps the next bug bounty hunter find this.

Follow me here for more on AI-augmented security workflows and bug bounty hunting.

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Tags: Bug Bounty · Cybersecurity · Claude AI · HackerOne · Penetration Testing