DEFCON 2011 Network Forensics Puzzle: The Heist
*Note* I am in no way affiliated with the contest and if you couldnt tell the post below contains my solution for the round
After extracting the contents from round_4.tc, you are left with a pcap and a html page outlining the challenge:
Inter0ptic arrived to Factory-Made-Winning, and casually made his way past the front security desk. He then slipped into a secure access area by tailgating behind an employee. On the way in he found a sticky note with a password on it “useonce@”. The password might come in handy later! With a grin and a chuckle, Inter0ptic found an empty cubical and plugged in his laptop.
Use the packet capture in this folder to learn more about Inter0ptic’s adventure at the pharmaceutical company and answer the question below:
1. What is the 16th name inside the mysterious file transfered?
After opening the file in WireShark you’ll notice a lot of SMB traffic. I noticed a file transferred with a 7z extension and figured I would attempt to carve it out. Again, I had to look up the file signatures for 7z.
I used tcpxtract again.
echo "p7z(100000000, \x37\x7a\xbc\xaf\x27\x1c);" > /etc/tcpxtract.conf
tcpxtract -f ~/Evidence04.pcap
mv 00000000.p7z 00000000.7z
Notice the p7z extension in the tcpxtract.conf? For whatever reason tcpxtract didnt like the fact that I had an integrer as the first character on the line. So I added p7z and it worked fine. I just had to change the extension back if I wanted this file to work on Winblows.
Once I opened the file I noticed a xls file. I tried extracting the file but the archive was password protected. nooooooooooooooo. But wait, we have a password………Yeah I tried useonce@ too. It didnt work. After scratching my head for a bit someone had the bright idea to try Romulus’ password. That worked….herp derp. Thank Ryan.