DRG - FIRST 2013 Challenge - Network2 500

Question:

Network2 500

What is the challenge?

Answer:

1. Th1s i5 the DRG cha113nge

Solution:

1. First, we got a .pcap file named "e4a33f65d429e48819c842d745c0af18ce6c6cb95063de12116f29fb1d455506.pcap" from the challenge website.
2. After we opened it, we could discover that there was a PNG image file inside the pcap file.
   

   

   
   

3. Saved the raw content into a PNG file. Opened it and we got a QR code image like below.
   

   

   
   

4. After we decoded the QR code, we got another base64 string.
   

   Tool: http://zxing.org/w/decode.jspx
   
   Base64 string:
   VGgxcyBpNSB0aGUgRFJHIGNoYTExM25nZQo9PT09PT09PT09PT09PT09PT09PT09PT09ClR3aXR0 ZXIgaXMgYSBncmVhdGVmdWwgdG9vbCB0byBzcHJlYWQgeW91ciB0aG91Z2h0cy4KWW91IHNob3Vs ZCBiZSBjYXJlZnVsIHdoYXQgeW91IHR3ZWV0LgpAdG9tZGZjMQo=

5. Using online tools to decode the base64 string.
   

   Tool: http://www.motobit.com/util/base64-decoder-encoder.asp
   
   Result:
   Th1s i5 the DRG cha113nge
   =========================
   Twitter is a greateful tool to spread your thoughts.
   You should be careful what you tweet.
   @tomdfc1

6. We got it!