Security and Hardening
An OWASP-driven security review skill that hardens user input, auth, dependencies, and LLM features with concrete code patterns.
Security & ReviewIntermediate★ 422⑂ 44AI score 8/10Last updated: Sep 12, 2026
What it does
- Threat model first: maps trust boundaries (HTTP requests, uploads, webhooks, LLM output, even another process's argv), runs a quick STRIDE pass, and turns abuse cases into your first tests.
- Three-tier rule system: Always Do (validate input, parameterize queries, hash passwords, security headers), Ask First (new auth flows, CORS changes, file uploads), Never Do (commit secrets, log sensitive data,
eval/innerHTMLwith user data). - OWASP Top 10 prevention patterns with TypeScript snippets for injection, broken auth, XSS, access control, misconfiguration, data exposure, and SSRF (including a private-IP resolution check).
- Dependency & supply-chain triage: a decision tree for audit findings by severity and reachability, blocking install scripts, verifying signatures/provenance, spotting typosquats.
- AI/LLM security & privacy: treat model output as untrusted, resist prompt injection, bound token/loop consumption, classify personal data, set retention and working deletion paths for GDPR/CCPA.
- Review checklists and red flags for auth, authorization, input, data, infra, supply chain, and LLM usage.
Who it's for
- Web developers (especially Node/TypeScript, Express, Next.js) doing self-review before shipping
- Teams building login, sessions, payments, or anything touching PII
- Engineers who need a defensible rule for when an audit finding blocks a release
- Anyone adding chatbot/RAG features and worried about the new attack surface
Examples
- "Audit this login flow against the OWASP Top Ten" → checks cookie flags, rate limiting, hash cost, and whether errors leak internals.
- "
npm auditshows three high findings — do I block the release?" → walks the decision tree on reachability, dev-only vs runtime, and fix availability, and records a review date for deferrals. - "We fetch images from a user-supplied URL" → produces scheme/host allowlisting, private-IP rejection,
redirect: 'error', plus the DNS-rebinding TOCTOU caveat.
· · · Install guide · · ·
Try it now, no install
Paste this into Claude to use the skill without installing anything.
Read the instructions in this file and follow them to help me: https://raw.githubusercontent.com/aiskillstore/marketplace/HEAD/pending/addyosmani/security-and-hardening/SKILL.md What I want: (describe your task here)
If Claude can't open the link, open it yourself and paste the contents instead.
↓ If it works for you, download the ZIP below and install it. Then it runs on its own — no pasting each time.
Install in the Claude app (no terminal)
- Download the ZIP with the button below.
- In Claude, open Settings → Capabilities and turn on 'Code execution and file creation'. (one time)
- Go to Customize → Skills → + → 'Upload a skill' and upload the ZIP.
Install in Claude Code
Let Claude do it — paste this into Claude Code
Install the skill I found on Claude Skill Mart. Copy the pending/addyosmani/security-and-hardening folder from the GitHub repo aiskillstore/marketplace into my ~/.claude/skills/security-and-hardening/. When it's done, tell me in one line what this skill can do.
Install with a command instead
git clone https://github.com/aiskillstore/marketplace /tmp/aiskillstore && mkdir -p ~/.claude/skills/security-and-hardening && cp -r /tmp/aiskillstore/pending/addyosmani/security-and-hardening/* ~/.claude/skills/security-and-hardening/⚠ This is a third-party skill. Check the source repository before installing.
- Open a terminal.
- Create the skills directory:
mkdir -p ~/.claude/skills - Clone the repository into a temp folder:
git clone https://github.com/aiskillstore/marketplace /tmp/aiskillstore - Copy the skill:
cp -r /tmp/aiskillstore/pending/addyosmani/security-and-hardening ~/.claude/skills/ - If the repo ships
references/security-checklist.md(referenced by the skill), copy it to~/.claude/references/so the links resolve. - Verify:
ls ~/.claude/skills/security-and-hardening/SKILL.md - Restart Claude Code and ask something like "review this API route's input handling for vulnerabilities" to trigger the skill.