# Insanity Check

## Challenge Information

• Category: Miscellaneous
• Points: 200
• Solves: 47
• Difficulty: Insane (maybe not)

## Description

You might've breezed through the easy Sanity Check, but this challenge is for true contenders! If you want to prove your sanity is as unhinged as mine, you’ll have to earn it.

How, you ask?

Back when we were building these CTF challenges, everyone would upload their carefully crafted puzzles, and I was the one reviewing them. But me being me—I rejected a ton of them, tossing them straight into the bin for all sorts of reasons. Naturally, my teammates started questioning my sanity, some even calling me insane. But if there was one thing that remained constant, it was the bin. Now, it’s your turn to dig in and you already know where to start... The same place where you proved you were sane!

I think you must be in the Discord server by now - https://discord.gg/BWYPxRQPSd

## Approach

I'd looked through every channel on the Discord server, searched through the server using the search term for the flag format, revealed nothing. People were trying various bots present in the server to see if they'd reveal the flag. There was nothing. It did occur to me that maybe it could be hidden in the roles or bio of a user in the server but there were over 1000 people in the Discord server and I did not bother trying until I came back to the challenge and finally decided to finish it after the challenge organizers released a hint related to the challenge.

### Hint

Insanity Check: You might have found this weird string "r8F53sXv", but who owns it?

This obviously meant that a particular user had a role with that string but it was still too much to manually check.

## Reverse Engineering

I went through my own Discord server and tried to see what request Discord would send when I tried to view the role info in server settings to see members who had a particular role.

The request was sent to this URL

https://discord.com/api/v9/guilds/[SERVERID]/roles/[ROLEID]/member-ids

I used the appropriate server ID and the role ID for the r8F53sXv role and found the user account that had it. It was a user with display name PasteBin (username: pastebin0459_24128)

## Solution

Obviously Pastebin links wouldn't be of that format having only numbers in the / endpoint. I tried the original role string and navigated to:

https://pastebin.com/r8F53sXv

That revealed the flag and the solution of this challenge.

## Flag

ACECTF{7h47_w45_1n54n3}