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Forbidden | Web

183 words·1 min·
0xShakhawat
Author
0xShakhawat
Table of Contents

CTF NAME: Forbidden
#

Point: 275 (dynamic point)
Category: Web
Description:
Hackers love forbidden things

http://<IP>:4041/

Flag: CBCTF{d0n7_4fr41d_0f_3ncryp7ed_c00ki35}

Solve:
This was an interesting one. I struggled a lot and learned a lot. It took more than 2 hours to solve. And It is worth the time.

The web is just a blank page. The response of the page is 403 Forbidden.

I followed and tried what I knew and everything mentioned on HackTricks’s “403 & 401 Bypasses” page. But I can’t solve the challenge.

Then I have done a bunch of random things. Then I played with cookie, after done some things, I noticed the cookie value looks like a hash.

Cookie: 7cb6efb98ba5972a9b5090dc2e517fe14d12cb04

Then I gave it to the “dcode.fr”

“Dcode.fr” said It probably SHA-1 hash.

Then I decoded the Hash.

The Decrypted value is “false”. So I Encrypted “true” to SHA-1.

Then I set it on the cookie value for the web site.

The cookie value for “true” in SHA-1 Hash is: 5ffe533b830f08a0326348a9160afafc8ada44db

After refreshing the page I got the flag.

I also tried with the burp.

It was an interesting CTF.