• ✅ JWT secrets moved to environment variables
• ✅ Database credentials externalized
• ✅ API keys externalized
• ✅ Created env.example template for secure configuration

• ✅ Frontend input validation (username, password, IBAN, amount)
• ✅ XSS prevention with HTML entity encoding
• ✅ Backend input validation with length and format checks
• ✅ SQL injection prevention with parameterized queries

• ✅ Sanitized error messages to prevent information disclosure
• ✅ Generic error responses for security events
• ✅ Proper logging without exposing sensitive data

• ✅ Bucket4j implementation with Redis backend
• ✅ Configurable rate limits (60 requests/minute default)
• ✅ Burst capacity protection (100 requests default)
• ✅ Health check endpoint exclusion

• ✅ SSL/TLS configuration
• ✅ Security headers (X-Content-Type-Options, X-Frame-Options, etc.)
• ✅ Content Security Policy (CSP)
• ✅ HSTS (HTTP Strict Transport Security)
• ✅ Secure cookie configuration

Create a .env file based on env.example:

# Database Configuration
POSTGRES_PASSWORD=your-secure-password-here

# JWT Configuration
JWT_SECRET=your-super-secure-jwt-secret-key-here

# API Configuration
API_KEY=your-secure-api-key-here

# Security Configuration
CORS_ALLOWED_ORIGINS=https://yourdomain.com
RATE_LIMIT_REQUESTS_PER_MINUTE=60

For development, generate a self-signed certificate:

keytool -genkeypair -alias tomcat -keyalg RSA -keysize 2048 -storetype PKCS12 -keystore keystore.p12 -validity 3650

• Input validation and sanitization
• XSS prevention
• Secure API communication
• Content Security Policy compliance

• JWT token validation
• Rate limiting per IP
• Input validation and sanitization
• Secure error handling
• Security headers

• Parameterized queries
• Connection encryption
• Credential externalization

• 60 requests per minute per IP
• 100 request burst capacity
• Redis-based tracking

• Security events logged
• Failed login attempts tracked
• Rate limit violations monitored

1. Test rate limiting by making rapid requests
2. Verify input validation with malicious inputs
3. Check security headers in browser dev tools
4. Test XSS prevention with script injection

# Test rate limiting
for i in {1..70}; do curl -X POST http://localhost:8080/api/auth/login -H "Content-Type: application/json" -d '{"username":"test","password":"test"}'; done

# Test input validation
curl -X POST http://localhost:8080/api/auth/login -H "Content-Type: application/json" -d '{"username":"<script>alert(1)</script>","password":"test"}'

1. Generate proper SSL certificates
2. Update CORS origins to production domains
3. Set strong, unique secrets
4. Configure proper logging levels
5. Enable security monitoring

• All secrets externalized
• HTTPS enabled
• Security headers configured
• Rate limiting active
• Input validation working
• Error handling secure
• Logging configured
• Monitoring enabled

• OAuth2/OpenID Connect integration
• Multi-factor authentication
• Advanced threat detection
• Security audit logging
• Penetration testing
• Security scanning automation

1. Immediately revoke compromised tokens
2. Check logs for suspicious activity
3. Update all secrets and keys
4. Notify security team
5. Document incident

• Check for legitimate traffic spikes
• Verify no DDoS attack
• Adjust rate limits if needed
• Monitor for patterns

⚠️ Important: This security implementation provides a solid foundation, but security is an ongoing process. Regular security audits, updates, and monitoring are essential for maintaining a secure application.