Write-up – Steganography 50 – Newbie challenge

Points: 50
Author: …

We are provided with an archive containing one unique file : newbie_challenge.pgm

Opening it shows us :

We tried some classic tools such as foremost an binwalk without success.

Then, we opened the file into bless and saw this :

Interesting! The hex contains : “Fuck ! So close to one byte !”

Time to go online and look at pgm file extension => wikipedia – Portable Pixmap

Ok, so let’s try to edit first byte value from p5 to p6 and open the file with an image viewer!

Flag : GH17{d0Nt_B3_C0loR_bl1ND}

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