Spring Open Redirect Guide: Examples and Prevention

Websites and applications increasingly tailor experiences to individual users, necessitating data for controlling user flow and permitted actions, such as redirecting users to other pages. Open redirect vulnerabilities occur when redirection links are visible in a URL, exposing users to phishing attacks by redirecting them to potentially malicious external sites. To mitigate this risk, the article explores how to protect users from open redirects using Spring, focusing on methods such as intercepting requests with MVC controllers, applying filters, and implementing exit pages. A sample Spring Boot application with Thymeleaf illustrates these techniques, demonstrating how developers can manage redirection securely. By configuring redirects and using filters, developers can either block or approve requests based on domain checks, while exit pages can inform users when they are navigating away from the application. This approach adds an additional security layer, ensuring not only the protection of user information but also the integrity of their browsing experience.