This document outlines the security measures implemented in the AI Kids Learning platform.

Implementation: Middleware-based rate limiting

• API Routes: 100 requests per minute per IP
• Authentication: 5 requests per 5 minutes per IP
• Payment Routes: 10 requests per minute per IP

Headers:

• X-RateLimit-Limit: Maximum requests allowed
• X-RateLimit-Remaining: Requests remaining
• X-RateLimit-Reset: When the limit resets
• Retry-After: Seconds to wait before retrying (on 429)

Implemented Headers:

• Strict-Transport-Security: Forces HTTPS
• Content-Security-Policy: Prevents XSS attacks
• X-Frame-Options: Prevents clickjacking
• X-Content-Type-Options: Prevents MIME sniffing
• Referrer-Policy: Controls referrer information
• X-XSS-Protection: Browser XSS protection
• Permissions-Policy: Restricts browser features

Validation Library: Zod

Validated Inputs:

• Child profiles (name, age, avatar_color, learning_level)
• Progress tracking (child_id, activity_id, score, time_spent)
• Email addresses
• Passwords (min 8 chars, uppercase, lowercase, number)

Sanitization:

• HTML entity encoding
• String length limits
• Character whitelisting for names

Implementation: Supabase Auth + Row Level Security (RLS)

Protected Routes:

• All /api/* routes require authentication
• /parent/* routes require parent authentication
• /kids/* routes require authentication

Session Management:

• Automatic session refresh in middleware
• Secure cookie handling
• HTTP-only cookies

Row Level Security (RLS):

• Users can only access their own data
• Children profiles linked to parent_id
• Progress data linked to child_id
• Subscriptions linked to user_id

Query Security:

• Parameterized queries (Supabase client)
• No raw SQL from user input
• Service role client only for admin operations

Authentication:

• JWT tokens via Supabase
• Token validation on every request
• Automatic token refresh

Authorization:

• User can only access their own children
• User can only modify their own data
• Admin operations require service role

Audit Logging:

• User actions logged
• IP address tracking
• Timestamp recording
• Metadata capture

Stripe Integration:

• PCI DSS compliant (Stripe handles card data)
• Webhook signature verification
• Secure API key storage
• Rate limiting on payment endpoints

Environment Variables:

• STRIPE_SECRET_KEY: Server-side only
• STRIPE_WEBHOOK_SECRET: Webhook verification
• NEXT_PUBLIC_STRIPE_PUBLISHABLE_KEY: Client-side (safe)

Children's Data Protection:

• Parental consent required
• No direct data collection from children
• Secure data storage
• Data deletion on request
• Privacy policy compliance

Never commit:

• API keys
• Database credentials
• Webhook secrets
• Service role keys

Use:

• Vercel environment variables
• .env.local for local development
• NEXT_PUBLIC_* prefix only for client-safe variables

Do:

• Validate all user input
• Sanitize HTML output
• Use parameterized queries
• Implement rate limiting
• Log security events
• Keep dependencies updated

Don't:

• Trust user input
• Expose sensitive data in errors
• Use eval() or similar
• Store secrets in code
• Disable security features

1. Assess Impact: Determine severity and affected users
2. Contain: Disable affected features if necessary
3. Fix: Implement and test fix
4. Deploy: Push fix to production immediately
5. Notify: Inform affected users if required
6. Document: Record incident and response

Email: security@kids-learning-ai.com (TODO: Set up)

• Rate limiting implemented
• Security headers configured
• Input validation on all forms
• Authentication on protected routes
• Row Level Security (RLS) enabled
• CSRF protection (via Supabase)
• XSS prevention (sanitization)
• SQL injection prevention (parameterized queries)
• Secure session management
• Audit logging
• HTTPS enforced (HSTS)
• Environment variables secured
• Security monitoring (TODO: Add Sentry/monitoring)
• Regular security audits (TODO: Schedule)
• Penetration testing (TODO: Before launch)

1. Redis-based Rate Limiting: For distributed systems
2. Advanced Monitoring: Sentry, LogRocket, or similar
3. 2FA: Two-factor authentication for parents
4. IP Whitelisting: For admin operations
5. Automated Security Scans: GitHub Dependabot, Snyk
6. WAF: Web Application Firewall (Cloudflare)
7. DDoS Protection: Advanced rate limiting
8. Security Headers Testing: Regular audits

• COPPA: Children's Online Privacy Protection Act
• GDPR: General Data Protection Regulation (if EU users)
• PCI DSS: Payment Card Industry Data Security Standard (via Stripe)

• OWASP Top 10
• Next.js Security
• Supabase Security
• Stripe Security