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

Lab: Exploiting HTTP request smuggling to bypass front-end security controls, CL.TE vulnerability


This lab involves a front-end and back-end server, and the front-end server doesn't support chunked encoding. There's an admin panel at /admin, but the front-end server blocks access to it.

To solve the lab, smuggle a request to the back-end server that accesses the admin panel and deletes the user carlos.


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.

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