Thecybergrabs CTF : Forensic challenge : cat

Recently i participated in “Thecybergrabs CTF”. I found “cat” challenge interesting in Forensic challenge.

“cat” challenge was bit tricky. so let’s see how i solved this challenge.

Challenge : cat

As we can see we have to download one image file (cat.png).

cat.png

So first thing i did was a google search and search string i used was “online qr code reader from image”. i navigate to “https://zxing.org/w/decode.jspx” website and uploaded cat.png.

scan result for cat.png

OOPS we didn’t get anything. “YOU ARE WRONG !!!!!”

second thing i tried was “Online metadata and exif viewer” for this i used following website : http://metapicz.com/. i uploaded cat.png file and i found some interesting comment.

exif viwer

we found User Comment “OUR CTF MEMEBER HAS SUBMITTED SOMETHING ON HIS TWITTER”.

So i was searching ctf members profile and i found some interesting string in one of the profile.

So we found Cat : NB2HI4DTHIXS64DBON2GKYTJNYXGG33NF52UG5ZZGNMEU5Q=

At first look i guessed this is “Base32 string”. So i tried to decode it online. ( website i used was : https://emn178.github.io/online-tools/base32_decode.html)

Base32 decode

Yaas, we can see we found one link. ( https://pastebin.com/uCw93XJv

So i visited “https://pastebin.com/uCw93XJv” this link.

pastebin link

“if you find me then the flag is my management company’s name”

OO, one more link. So when i visited given google drive link i found this photo

Catriona Gray

By help of google image search i found that she is “Catriona Gray” (2018 Miss Universe)

so now what i did was just google search for “Catriona Gray official website”. i found following url : www.catrionagray.ph

Now in official website i navigate to contact page

contact page of www.catrionagray.ph

Yaas we found the name of the Management team. (Cornerstone Entertainment)

flag{CornerstoneEntertainment}

Really Great CTF by thecybergrabs.

(This is my first attempt in CTF write-up. Suggestions are welcome)