Post

POSTAL

Description

My Australian friend “Bob” wants to send me a secret, but he is scared of attackers. He told me that he knows some forensics tricks and sent me this image, would you help to reveal his message?

Note: Part of this challenge is inspired by Going Postal challenge from DaVinciCTF 2022.

Steps

when opening the attached msg.jpg we can see that there is an **Australia Post 4-State Barcode **at the top. by entering the barcode in the image ATDFFDDADDAADAADFAFAFFAFATAFAAATADTAFDTDDDDDDDTTTTTTTTADAFFFAFAAAAT

we get the following data

Untitled

by running the command steghide extract -sf msg.jpg -p K4N64r00zz using the customer information we just got from the Post Barcode

Untitled

we get a password locked .zip file.

we can then try to unlock the file using john

zip2john ./POSTAL/Treasure.zip > johnfile

john --wordlist=/usr/share/wordlists/rockyou.txt johnfile

we get the password baltimore

which can be used to view the text file and the flag.gpg

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nice you are close 
do you know gpg....?
I think you have the password just get back to your notes :)

so we know we have already found the password somewhere.

trying out the values we got from the Australian post barcode we find that the password is 78475110

we just need to decrypt the gpg encrypted flag with the password and submit it

Flag

CyberErudites{4U57r4114_P057_4_57473}


This post is licensed under CC BY 4.0 by the author.