HTTP request smuggling is a web attack technique that exploits inconsistencies in the way different servers or components (like proxies and front-end/back-end servers) handle HTTP requests. By crafting malicious requests using conflicting headers (such as `Content-Length` and `Transfer-Encoding`), attackers can "smuggle" hidden requests past security controls. This can lead to various issues, including cache poisoning, session hijacking, and unauthorized access, making it a serious threat in modern web applications.
Scenario:
You are a penetration tester auditing the web application craw.in. You've identified a potential discrepancy in how the front-end server and the back-end server are interpreting HTTP requests. Your goal is to exploit this difference.