security-audit

name	security-audit
description	Use when auditing a codebase before it goes public-facing, after a lab build, or on any periodic security pass. Checks secrets in code and history (including Claude Code transcripts), authorization and RLS, input validation, dependency red flags, and exposed endpoints.

Security Audit

Run this in a FRESH session. An auditor that helped write the code shares its blind spots. Zero context is the feature: /clear first, or open a new session, then invoke this skill.

Work through all five fronts. For each finding report: severity (critical/high/medium/low), file and line, the attack it enables, and the fix. No hand-waving; every finding gets a concrete fix.

1. Secrets in code and history

• Grep the working tree for key patterns: sk-, sk_live, AKIA, ghp_, -----BEGIN, password\s*=, token\s*= with literal values.
• Check git history, not just HEAD: git log -p | grep for the same patterns. A key deleted in a later commit is still leaked.
• Check .env is gitignored and no .env* file is tracked.
• The one everyone misses: Claude Code transcripts. Every paste lands in ~/.claude session JSONL files forever. Search them: grep -rl "sk-\|sk_live\|AKIA" ~/.claude/projects/ 2>/dev/null. If keys appear, instruct the user to rotate them. Deleting the transcript does not unleak a key.

2. Authorization and RLS

• Every endpoint that reads or writes user data: where is the ownership check? "The frontend only shows your own data" is not a check.
• Supabase/Postgres: confirm RLS is enabled on every table with user data and policies are default-deny. List any table where RLS is off.
• Look for IDs accepted from the client and used in queries without verifying the session user owns them.

3. Input validation

• Every external input (request bodies, query params, webhooks, file uploads): is it validated at the boundary with a schema, or trusted?
• Raw string interpolation into SQL, shell commands, or HTML.
• File uploads: type, size, and path checks.

4. Dependencies

• Scan recently added dependencies for typosquats: names one edit away from popular packages (models hallucinate package names; attackers pre-register the typos). Verify each new package exists on the registry with real download numbers and a real repo.
• Flag packages with install scripts doing anything unusual.
• Run the ecosystem's audit command (pnpm audit, pip-audit) and triage criticals.

5. Exposed endpoints

• Enumerate every route. For each: is it meant to be public? Debug routes, admin panels, /dev/* prototypes, and webhook endpoints without signature verification all count as findings.
• Check CORS configuration and any wildcard origins.
• Confirm secrets are not shipped to the client bundle (search build output for key patterns).

Output

A findings table sorted by severity, then a "fix now" list of the top 3. Offer to fix the top finding immediately.