1. Web Security Academy
  2. Request smuggling
  3. Finding
  4. Lab

Lab: HTTP request smuggling, confirming a CL.TE vulnerability via differential responses

PRACTITIONER

This lab involves a front-end and back-end server, and the front-end server doesn't support chunked encoding.

To solve the lab, smuggle a request to the back-end server, so that a subsequent request for / (the web root) triggers a 404 Not Found response.

Hint

Manually fixing the length fields in request smuggling attacks can be tricky. Our HTTP Request Smuggler Burp extension was designed to help. You can install it via the BApp Store.