{
  "schema": "https://ai-atoms.com/schemas/skill-v1.json",
  "type": "skill",
  "id": "skill/cc-skill-security-review",
  "version": "1.0.0",
  "name": "Cc Skill Security Review",
  "description": "Use this skill when adding authentication, handling user input, working with secrets, creating API endpoints, or implementing payment/sensitive features. Provides comprehensive security checklist a...",
  "system_prompt_fragment": "# Security Review Skill\n\nThis skill ensures all code follows security best practices and identifies potential vulnerabilities.\n\n## When to Activate\n\n- Implementing authentication or authorization\n- Handling user input or file uploads\n- Creating new API endpoints\n- Working with secrets or credentials\n- Implementing payment features\n- Storing or transmitting sensitive data\n- Integrating third-party APIs\n\n## Security Checklist\n\n### 1. Secrets Management\n\n#### ❌ NEVER Do This\n```typescript\nconst apiKey = \"sk-proj-xxxxx\"  // Hardcoded secret\nconst dbPassword = \"password123\" // In source code\n```\n\n#### ✅ ALWAYS Do This\n```typescript\nconst apiKey = process.env.OPENAI_API_KEY\nconst dbUrl = process.env.DATABASE_URL\n\n// Verify secrets exist\nif (!apiKey) {\n  throw new Error('OPENAI_API_KEY not configured')\n}\n```\n\n#### Verification Steps\n- [ ] No hardcoded API keys, tokens, or passwords\n- [ ] All secrets in environment variables\n- [ ] `.env.local` in .gitignore\n- [ ] No secrets in git history\n- [ ] Production secrets in hosting platform (Vercel, Railway)\n\n### 2. Input Validation\n\n#### Always Validate User Input\n```typescript\nimport { z } from 'zod'\n\n// Define validation schema\nconst CreateUserSchema = z.object({\n  email: z.string().email(),\n  name: z.string().min(1).max(100),\n  age: z.number().int().min(0).max(150)\n})\n\n// Validate before processing\nexport async function createUser(input: unknown) {\n  try {\n    const validated = CreateUserSchema.parse(input)\n    return await db.users.create(validated)\n  } catch (error) {\n    if (error instanceof z.ZodError) {\n      return { success: false, errors: error.errors }\n    }\n    throw error\n  }\n}\n```\n\n#### File Upload Validation\n```typescript\nfunction validateFileUpload(file: File) {\n  // Size check (5MB max)\n  const maxSize = 5 * 1024 * 1024\n  if (file.size > maxSize) {\n    throw new Error('File too large (max 5MB)')\n  }\n\n  // Type check\n  const allowedTypes = ['image/jpeg', 'image/png', 'image/gif']\n  if (!allowedTypes.includes(file.type)) {\n    throw new Error('Invalid file type')\n  }\n\n  // Extension check\n  const allowedExtensions = ['.jpg', '.jpeg', '.png', '.gif']\n  const extension = file.name.toLowerCase().match(/\\.[^.]+$/)?.[0]\n  if (!extension || !allowedExtensions.includes(extension)) {\n    throw new Error('Invalid file extension')\n  }\n\n  return true\n}\n```\n\n#### Verification Steps\n- [ ] All user inputs validated with schemas\n- [ ] File uploads restricted (size, type, extension)\n- [ ] No direct use of user input in queries\n- [ ] Whitelist validation (not blacklist)\n- [ ] Error messages don't leak sensitive info\n\n### 3. SQL Injection Prevention\n\n#### ❌ NEVER Concatenate SQL\n```typescript\n// DANGEROUS - SQL Injection vulnerability\nconst query = `SELECT * FROM users WHERE email = '${userEmail}'`\nawait db.query(query)\n```\n\n#### ✅ ALWAYS Use Parameterized Queries\n```typescript\n// Safe - parameterized query\nconst { data } = await supabase\n  .from('users')\n  .select('*')\n  .eq('email', userEmail)\n\n// Or with raw SQL\nawait db.query(\n  'SELECT * FROM users WHERE email = $1',\n  [userEmail]\n)\n```\n\n#### Verification Steps\n- [ ] All database queries use parameterized queries\n- [ ] No string concatenation in SQL\n- [ ] ORM/query builder used correctly\n- [ ] Supabase queries properly sanitized\n\n### 4. Authentication & Authorization\n\n#### JWT Token Handling\n```typescript\n// ❌ WRONG: localStorage (vulnerable to XSS)\nlocalStorage.setItem('token', token)\n\n// ✅ CORRECT: httpOnly cookies\nres.setHeader('Set-Cookie',\n  `token=${token}; HttpOnly; Secure; SameSite=Strict; Max-Age=3600`)\n```\n\n#### Authorization Checks\n```typescript\nexport async function deleteUser(userId: string, requesterId: string) {\n  // ALWAYS verify authorization first\n  const requester = await db.users.findUnique({\n    where: { id: requesterId }\n  })\n\n  if (requester.role !== 'admin') {\n    return NextResponse.json(\n      { error: 'Unauthorized' },\n      { status: 403 }\n    )\n  }\n\n  // Proceed with deletion\n  await db.users.delete({ where: { id: userId } })\n}\n```\n\n#### Row Level Security (Supabase)\n```sql\n-- Enable RLS on all tables\nALTER TABLE users ENABLE ROW LEVEL SECURITY;\n\n-- Users can only view their own data\nCREATE POLICY \"Users view own data\"\n  ON users FOR SELECT\n  USING (auth.uid() = id);\n\n-- Users can only update their own data\nCREATE POLICY \"Users update own data\"\n  ON users FOR UPDATE\n  USING (auth.uid() = id);\n```\n\n#### Verification Steps\n- [ ] Tokens stored in httpOnly cookies (not localStorage)\n- [ ] Authorization checks before sensitive operations\n- [ ] Row Level Security enabled in Supabase\n- [ ] Role-based access control implemented\n- [ ] Session management secure\n\n### 5. XSS Prevention\n\n#### Sanitize HTML\n```typescript\nimport DOMPurify from 'isomorphic-dompurify'\n\n// ALWAYS sanitize user-provided HTML\nfunction renderUserContent(html: string) {\n  const clean = DOMPurify.sanitize(html, {\n    ALLOWED_TAGS: ['b', 'i', 'em', 'strong', 'p'],\n    ALLOWED_ATTR: []\n  })\n  return <div dangerouslySetInnerHTML={{ __html: clean }} />\n}\n```\n\n#### Content Security Policy\n```typescript\n// next.config.js\nconst securityHeaders = [\n  {\n    key: 'Content-Security-Policy',\n    value: `\n      default-src 'self';\n      script-src 'self' 'unsafe-eval' 'unsafe-inline';\n      style-src 'self' 'unsafe-inline';\n      img-src 'self' data: https:;\n      font-src 'self';\n      connect-src 'self' https://api.example.com;\n    `.replace(/\\s{2,}/g, ' ').trim()\n  }\n]\n```\n\n#### Verification Steps\n- [ ] User-provided HTML sanitized\n- [ ] CSP headers configured\n- [ ] No unvalidated dynamic content rendering\n- [ ] React's built-in XSS protection used\n\n### 6. CSRF Protection\n\n#### CSRF Tokens\n```typescript\nimport { csrf } from '@/lib/csrf'\n\nexport async function POST(request: Request) {\n  const token = request.headers.get('X-CSRF-Token')\n\n  if (!csrf.verify(token)) {\n    return NextResponse.json(\n      { error: 'Invalid CSRF token' },\n      { status: 403 }\n    )\n  }\n\n  // Process request\n}\n```\n\n#### SameSite Cookies\n```typescript\nres.setHeader('Set-Cookie',\n  `session=${sessionId}; HttpOnly; Secure; SameSite=Strict`)\n```\n\n#### Verification Steps\n- [ ] CSRF tokens on state-changing operations\n- [ ] SameSite=Strict on all cookies\n- [ ] Double-submit cookie pattern implemented\n\n### 7. Rate Limiting\n\n#### API Rate Limiting\n```typescript\nimport rateLimit from 'express-rate-limit'\n\nconst limiter = rateLimit({\n  windowMs: 15 * 60 * 1000, // 15 minutes\n  max: 100, // 100 requests per window\n  message: 'Too many requests'\n})\n\n// Apply to routes\napp.use('/api/', limiter)\n```\n\n#### Expensive Operations\n```typescript\n// Aggressive rate limiting for searches\nconst searchLimiter = rateLimit({\n  windowMs: 60 * 1000, // 1 minute\n  max: 10, // 10 requests per minute\n  message: 'Too many search requests'\n})\n\napp.use('/api/search', searchLimiter)\n```\n\n#### Verification Steps\n- [ ] Rate limiting on all API endpoints\n- [ ] Stricter limits on expensive operations\n- [ ] IP-based rate limiting\n- [ ] User-based rate limiting (authenticated)\n\n### 8. Sensitive Data Exposure\n\n#### Logging\n```typescript\n// ❌ WRONG: Logging sensitive data\nconsole.log('User login:', { email, password })\nconsole.log('Payment:', { cardNumber, cvv })\n\n// ✅ CORRECT: Redact sensitive data\nconsole.log('User login:', { email, userId })\nconsole.log('Payment:', { last4: card.last4, userId })\n```\n\n#### Error Messages\n```typescript\n// ❌ WRONG: Exposing internal details\ncatch (error) {\n  return NextResponse.json(\n    { error: error.message, stack: error.stack },\n    { status: 500 }\n  )\n}\n\n// ✅ CORRECT: Generic error messages\ncatch (error) {\n  console.error('Internal error:', error)\n  return NextResponse.json(\n    { error: 'An error occurred. Please try again.' },\n    { status: 500 }\n  )\n}\n```\n\n#### Verification Steps\n- [ ] No passwords, tokens, or secrets in logs\n- [ ] Error messages generic for users\n- [ ] Detailed errors only in server logs\n- [ ] No stack traces exposed to users\n\n### 9. Blockchain Security (Solana)\n\n#### Wallet Verification\n```typescript\nimport { verify } from '@solana/web3.js'\n\nasync function verifyWalletOwnership(\n  publicKey: string,\n  signature: string,\n  message: string\n) {\n  try {\n    const isValid = verify(\n      Buffer.from(message),\n      Buffer.from(signature, 'base64'),\n      Buffer.from(publicKey, 'base64')\n    )\n    return isValid\n  } catch (error) {\n    return false\n  }\n}\n```\n\n#### Transaction Verification\n```typescript\nasync function verifyTransaction(transaction: Transaction) {\n  // Verify recipient\n  if (transaction.to !== expectedRecipient) {\n    throw new Error('Invalid recipient')\n  }\n\n  // Verify amount\n  if (transaction.amount > maxAmount) {\n    throw new Error('Amount exceeds limit')\n  }\n\n  // Verify user has sufficient balance\n  const balance = await getBalance(transaction.from)\n  if (balance < transaction.amount) {\n    throw new Error('Insufficient balance')\n  }\n\n  return true\n}\n```\n\n#### Verification Steps\n- [ ] Wallet signatures verified\n- [ ] Transaction details validated\n- [ ] Balance checks before transactions\n- [ ] No blind transaction signing\n\n### 10. Dependency Security\n\n#### Regular Updates\n```bash\n# Check for vulnerabilities\nnpm audit\n\n# Fix automatically fixable issues\nnpm audit fix\n\n# Update dependencies\nnpm update\n\n# Check for outdated packages\nnpm outdated\n```\n\n#### Lock Files\n```bash\n# ALWAYS commit lock files\ngit add package-lock.json\n\n# Use in CI/CD for reproducible builds\nnpm ci  # Instead of npm install\n```\n\n#### Verification Steps\n- [ ] Dependencies up to date\n- [ ] No known vulnerabilities (npm audit clean)\n- [ ] Lock files committed\n- [ ] Dependabot enabled on GitHub\n- [ ] Regular security updates\n\n## Security Testing\n\n### Automated Security Tests\n```typescript\n// Test authentication\ntest('requires authentication', async () => {\n  const response = await fetch('/api/protected')\n  expect(response.status).toBe(401)\n})\n\n// Test authorization\ntest('requires admin role', async () => {\n  const response = await fetch('/api/admin', {\n    headers: { Authorization: `Bearer ${userToken}` }\n  })\n  expect(response.status).toBe(403)\n})\n\n// Test input validation\ntest('rejects invalid input', async () => {\n  const response = await fetch('/api/users', {\n    method: 'POST',\n    body: JSON.stringify({ email: 'not-an-email' })\n  })\n  expect(response.status).toBe(400)\n})\n\n// Test rate limiting\ntest('enforces rate limits', async () => {\n  const requests = Array(101).fill(null).map(() =>\n    fetch('/api/endpoint')\n  )\n\n  const responses = await Promise.all(requests)\n  const tooManyRequests = responses.filter(r => r.status === 429)\n\n  expect(tooManyRequests.length).toBeGreaterThan(0)\n})\n```\n\n## Pre-Deployment Security Checklist\n\nBefore ANY production deployment:\n\n- [ ] **Secrets**: No hardcoded secrets, all in env vars\n- [ ] **Input Validation**: All user inputs validated\n- [ ] **SQL Injection**: All queries parameterized\n- [ ] **XSS**: User content sanitized\n- [ ] **CSRF**: Protection enabled\n- [ ] **Authentication**: Proper token handling\n- [ ] **Authorization**: Role checks in place\n- [ ] **Rate Limiting**: Enabled on all endpoints\n- [ ] **HTTPS**: Enforced in production\n- [ ] **Security Headers**: CSP, X-Frame-Options configured\n- [ ] **Error Handling**: No sensitive data in errors\n- [ ] **Logging**: No sensitive data logged\n- [ ] **Dependencies**: Up to date, no vulnerabilities\n- [ ] **Row Level Security**: Enabled in Supabase\n- [ ] **CORS**: Properly configured\n- [ ] **File Uploads**: Validated (size, type)\n- [ ] **Wallet Signatures**: Verified (if blockchain)\n\n## Resources\n\n- [OWASP Top 10](https://owasp.org/www-project-top-ten/)\n- [Next.js Security](https://nextjs.org/docs/security)\n- [Supabase Security](https://supabase.com/docs/guides/auth)\n- [Web Security Academy](https://portswigger.net/web-security)\n\n---\n\n**Remember**: Security is not optional. One vulnerability can compromise the entire platform. When in doubt, err on the side of caution.\n\n## When to Use\nThis skill is applicable to execute the workflow or actions described in the overview.",
  "applicable_domains": [
    "security"
  ],
  "category": "security",
  "invocation": [
    "/cc-skill-security-review"
  ],
  "authored_by": "affaan-m",
  "source_url": "https://claudeskills.in/skill/cc-skill-security-review",
  "provenance": {
    "source": "claudeskills.in",
    "source_url": "https://claudeskills.in/skill/cc-skill-security-review",
    "author": "affaan-m",
    "license": "unknown",
    "imported_at": "2026-09-03",
    "notes": "Aggregated by claudeskills.in from community GitHub lists."
  },
  "tags": [
    "claudeskills",
    "security"
  ],
  "lifecycle": "draft"
}