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Lag'n'Crash CTF: Tedious? Or is it?

March 14, 2021

Challenge Overview

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This challenge is under the Misc category.

My friend pranked me and hide my secret in one these!

A file named tedious.zip is attached. You can download it here.

Solution

Extracting the contents of tedious.zip, we get a file called tedious. This is another zip file that contains a QR directory. Within the QR directory is 4255 other files.

By sorting the files by size, we can find the odd one out:

1337.zip is the odd one out and has the smallest size

Extracting it, we realise that it is a png file containing a QR code. By scanning the QR code, we get the flag: LNC{IS_THlS_TH3_R3AL_0N3?}:

QR code displayed by 1337.zip


Joel Tio

Written by Joel Tio who develops anything he finds interesting and tries to fit math into them. Check out the home page or his GitHub!

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