Download file here
The organizers of the contest give us a pcap file. We open it and see many TCP protocol, this is data of audio that the organizers want us to hear.
So, we open Conversation of pcap file and select TCP tab , it only TCP transmissions .Then I dump it by follow Stream -> Save As file. The raw data have size 801 kb.
The next step requires experience we drop file in audacity and the software has display error.
Next step, we choose file -> import -> raw data
Last but not least, we listen carrefully to get the flag
Whitehat md5 of pcm underscore stream in and underscore and underscore twenty-fifteen all lowercase
WhiteHat md5 pcm_stream__in_2015
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