What are the security best practices for Spring Boot in large-scale systems?

Some of the best practices for security in Spring Boot applications in large systems include enabling HTTPS for secure communication, Spring Security to handle authentication and authorization, role-based access control. Validate user input to prevent injection attacks, and keep the dependencies up-to-date to patch vulnerabilities. Also, encrypt data for safe storage, and implement logging and monitoring for early detection to respond swiftly in case of a security breach. Lastly, leverage environment variables with secure configuration management for system integrity.