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

Lab: Exploiting HTTP request smuggling to capture other users' requests

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 that causes the next user's request to be stored in the application. Then retrieve the next user's request and use the victim user's cookies to access their account.

Note

The lab simulates the activity of a victim user. Every few POST requests that you make to the lab, the victim user will make their own request. You might need to repeat your attack a few times to ensure that the victim user's request occurs as required.

Tip

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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