ESGISECURITYDAY - Kubor
06 Apr 2018description: Kubor > Pssst Petit. Je t’ai contacté il y’a quelque jours pour resoudre cette enigme. Elle est beaucoup trop difficile pour moi !! Aide moi !!
category: Stegano
A .txt file was provided for this challenge, it was some 0 and 1. At first sight it seems to be a QRcode transposed into binary visualization.
0000000000000011110011000000111100111100001100000000000000
0011111111110011000011111100111111000000111100111111111100
0011000000110011110011110011001100000011111100110000001100
0011000000110011110000110000000000000011001100110000001100
0011000000110011110000110011110000001111001100110000001100
0011111111110011001100000011000011001100001100111111111100
0000000000000011001100110011001100110011001100000000000000
1111111111111111001100001111001111111111001111111111111111
1111111100000000111111111111110000111100001100001111110011
1100110011001100110011111100111100000000111100000000000011
1111110000110000111111110000000011000000110000111111111100
1111000000111111111100000011001111001100001100001100111100
1111000000001100000011000011000011001100110000110000111100
0000111111001100111111110011001111001111110011000000000000
1111111100000011111111000000110011001111111100110000000000
1100110000111111110011110011111111001111110011000000110011
0011111111110011000011001100001111001100001111001100000011
0000001111111111000000110011001111111100000000110000001111
1111001111000000001100000000001100000011000000001111001100
1111111100111100110011001100111111111111000011110000111100
0000110011110000000011110000000011000011000000000011000011
1111111111111111001100111111110000001111001111110011001100
0000000000000011000011110000110011110000001100110000001100
0011111111110011000000000000001111110011001111110000111111
0011000000110011000000110011001100111100000000000000000000
0011000000110011111100001100000000111111110011001111110011
0011000000110011111100111100111100000011110000111100000000
0011111111110011110000000011001100000000000000111100110000
0000000000000011110000110011111111110011000000111100110011Version 1
The first attempt was to replace “0” by “⬛” (Large Black Square Unicode), and “1” by “⬜” (Large White Square Unicode) inside my text editor. The result looked like this, but it wasn’t enough to scan the QR code with my Android.
⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛
⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛
⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛
⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛
⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛
⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛
⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛
⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜
⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜
⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜
⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛
⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛
⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛
⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛
⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛
⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜
⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜
⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜
⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛
⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛
⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜
⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛
⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛
⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜
⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛
⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜
⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛
⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛
⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬛⬛⬜⬜⬛⬛⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬛⬛⬛⬛⬜⬜⬜⬜⬛⬛⬜⬜⬛⬛⬜⬜
The next step, was to improve the QR code, we loaded it into Microsoft Paint an resize it to create a squared picture. Then we shrinked it, and we can scan the code with success.
Version 2
The previous version was working but unsatifying, I went back into the original idea of replacing characters.
cat qr | sed "s/1/█/g" | sed 's/0/ /g'And we have a clean QRcode ready to be scanned.
The flag was ESGI{QRC0d3_f0r_l1f3}
