AirTech CTF 2024 - Back To The Bases
A network forensics CTF chall. writeup.
Let's get Cracking...
Challenge 01: Back to the bases
There was a Wire Shark file given in order for us solve the challenge. You can also download the challenge file by clicking here
When I opened the file I noticed that there are some TCP
packets.
So without any delay I followed the TCP
Stream from Analyze > Follow > TCP Stream
menu. After following it I found the following chat.
As they are talking about a file. So I applied the FTP filter and found a flag.txt
file.
So I extracted it from File > Extract Object > FTP Data
.
After saving and opening the file I found the following text.
AFAi^Xd%^W ^TA ^XAj]j]j]!)btGBQZUQhvA--
Now if you remember from the chat there where two more leads as well.
- Can you pass me the
XOR
key. - ssure btw its
5
So I simply opened CyberChief and typed XOR
and used 05
as the key but sadly it didn't work.
But when you have a key you always have the option to Brute Force it. When I Brute Forced the cipher I found a base64 encoded string.
Simply decoded the string and got the flag.
Flag: AT24{y4m44444t33333_kud@$@1}
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