Secret Scanner Skill

Prevent accidental secret exposure in your codebase.

When I Activate

• ✅ Before git commits
• ✅ Files modified/saved
• ✅ User mentions secrets, keys, or credentials
• ✅ .env files changed
• ✅ Configuration files modified

What I Detect

API Keys & Tokens

• AWS access keys (AKIA...)
• Stripe API keys (sk_live_..., pk_live_...)
• GitHub tokens (ghp_...)
• Google API keys
• OAuth tokens
• JWT secrets

Database Credentials

• Database connection strings
• MySQL/PostgreSQL passwords
• MongoDB connection URIs
• Redis passwords

Private Keys

• SSH private keys
• RSA/DSA keys
• PGP/GPG keys
• SSL certificates

Authentication Secrets

• Password variables
• Auth tokens
• Session secrets
• Encryption keys

Alert Examples

API Key Detection

// You type:
const apiKey = 'sk_live_1234567890abcdef';

// I immediately alert:
🚨 CRITICAL: Exposed Stripe API key detected!
📍 File: config.js, Line 3
🔧 Fix: Use environment variables
  const apiKey = process.env.STRIPE_API_KEY;
📖 Add to .gitignore: .env

AWS Credentials

# You type:
aws_access_key = "AKIAIOSFODNN7EXAMPLE"

# I alert:
🚨 CRITICAL: AWS access key exposed!
📍 File: aws_config.py, Line 1
🔧 Fix: Use AWS credentials file or environment variables
  aws_access_key = os.getenv("AWS_ACCESS_KEY_ID")
📖 Never commit AWS credentials

Database Password

# You type in docker-compose.yml:
environment:
  DB_PASSWORD: "mySecretPassword123"

# I alert:
🚨 CRITICAL: Database password in configuration file!
📍 File: docker-compose.yml, Line 5
🔧 Fix: Use .env file
  DB_PASSWORD: ${DB_PASSWORD}
📖 Add .env to .gitignore

Detection Patterns

Pattern Types

High Confidence:

• Known API key formats (Stripe, AWS, etc.)
• Private key headers
• JWT tokens
• Connection strings with credentials

Medium Confidence:

• Variables named "password", "secret", "key"
• Base64 encoded strings in sensitive contexts
• Long random strings in assignments

Low Confidence (Flagged for Review):

• Generic secret patterns
• Potential credentials in comments

Git Integration

Pre-Commit Protection

# Before commit, I scan:
git add .
git commit

# I block if secrets found:
🚨 CRITICAL: Cannot commit - secrets detected!
📍 3 secrets found:
  - config.js:12 - API key
  - .env:5 - Database password (in gitignore - OK)
  - auth.js:45 - JWT secret

❌ Commit blocked - remove secrets first

.gitignore Validation

I check if sensitive files are in .gitignore:

✅ .env - In .gitignore (good)
⚠️ config/secrets.json - NOT in .gitignore (add it!)
✅ .aws/credentials - In .gitignore (good)

False Positive Handling

Example Files

// I understand these are examples:
// Example: const apiKey = 'your_api_key_here';
// TODO: Add your API key from environment

Test Files

// Test fixtures are OK (but flagged for review):
const mockApiKey = 'sk_test_1234567890abcdef';  // ✅ Test key

Documentation

<!-- Documentation examples are flagged but low priority -->
Set your API key: `export API_KEY=your_key_here`

Relationship with security-auditor

secret-scanner (me): Exposed secrets and credentials security-auditor: Code vulnerability patterns

Together

secret-scanner: Finds hardcoded API key
security-auditor: Finds how the key is used insecurely
Combined: Complete security picture

Quick Fixes

Move to Environment Variables

// Before:
const apiKey = 'sk_live_abc123';

// After:
const apiKey = process.env.API_KEY;

// .env file (add to .gitignore):
API_KEY=sk_live_abc123

Use Secret Management

// AWS Secrets Manager
const AWS = require('aws-sdk');
const secrets = new AWS.SecretsManager();
const secret = await secrets.getSecretValue({ SecretId: 'myApiKey' }).promise();

Configuration Files

# docker-compose.yml
services:
  app:
    environment:
      - API_KEY=${API_KEY}  # From .env file

# .env (gitignored)
API_KEY=sk_live_abc123

Sandboxing Compatibility

Works without sandboxing: ✅ Yes (recommended) Works with sandboxing: ✅ Yes

• Filesystem: Read-only access
• Network: None required
• Configuration: None required

Customization

Add company-specific secret patterns:

cp -r ~/.claude/skills/security/secret-scanner \
      ~/.claude/skills/security/company-secret-scanner

# Edit SKILL.md to add:
# - Internal API key formats
# - Company-specific secret patterns
# - Custom detection rules

Best Practices

1. Never commit secrets - Use environment variables
2. Use .gitignore - Add .env, secrets.json, etc.
3. Rotate exposed secrets - If committed, rotate immediately
4. Use secret management - AWS Secrets Manager, HashiCorp Vault
5. Audit regularly - Review code for exposed secrets

Emergency Response

If Secret Committed

1. Rotate the secret immediately
2. Remove from git history

   git filter-branch --force --index-filter \
     "git rm --cached --ignore-unmatch config/secrets.json" \
     --prune-empty --tag-name-filter cat -- --all
   

3. Force push (coordinate with team)
4. Update all deployments with new secret

Related Tools

• security-auditor skill: Vulnerability detection
• @code-reviewer sub-agent: Security review
• /review command: Comprehensive security check