• Python: Upgraded from 3.7.9 (EOL) to 3.11.9
• FastAI: Updated to 2.7.14
• PyTorch: Updated to 2.2.1
• All dependencies: Updated to latest secure versions

• File size limits (10MB max)
• File type validation (images only: JPEG, PNG, GIF, BMP, WebP)
• Filename sanitization
• Empty file checks

• 30 requests per minute per IP (configurable)
• In-memory rate limiting for DDoS protection

• Content-Security-Policy (CSP)
• X-Frame-Options: DENY
• X-Content-Type-Options: nosniff
• X-XSS-Protection: 1; mode=block
• Referrer-Policy: strict-origin-when-cross-origin

• Configurable allowed origins (no longer wildcard)
• Credentials support with specific origins

• Generic error messages to prevent information leakage
• Proper logging without exposing sensitive data
• Graceful model loading failures

• Non-root user execution
• Minimal base image (python:3.11.9-slim)
• Health checks included
• No cache for pip installations

• Environment variables for sensitive data
• .env file support with python-dotenv
• Example configuration file provided
• Model URL no longer hardcoded

Create a .env file based on .env.example:

PORT=5000
MODEL_URL=your_model_url_here
ALLOWED_ORIGINS=http://localhost:5000,https://yourdomain.com
MAX_FILE_SIZE_MB=10
RATE_LIMIT_PER_MINUTE=30

✅ Dependencies updated to latest versions ✅ Input validation on all user inputs ✅ Rate limiting implemented ✅ Security headers configured ✅ CORS properly configured ✅ Error handling prevents information leakage ✅ Docker container runs as non-root user ✅ Environment variables for configuration ✅ File size and type restrictions ✅ Request timeouts configured ✅ Health check endpoint available

The application includes:

• Structured logging with timestamps
• Health check endpoint at /health
• Error tracking with stack traces (in logs only)

1. Add authentication for production use
2. Implement database for persistent rate limiting
3. Add request signing/validation
4. Consider using a reverse proxy (nginx) in production
5. Implement monitoring and alerting
6. Add automated security scanning in CI/CD
7. Regular dependency updates schedule
8. Consider implementing CAPTCHA for additional bot protection