Forensics: Extraction of email evidence using Wireshark and NetworkMiner

The video at the end of this post is a demo of a solution to a forensic challenge from this site.

The goal of the challenge is to extract necessary information for an investigation from a pcap file. the site, forensicscontest.com, has a number of similar challenges that you can try out as well.

Obviously, there is more than one way to skin a pcap (the other methods can be found among the solutions/walkthroughs on the site itself) and in this case 2 tools were used:

Just to cover a few "mysterious" sections of the video, there is a point where I sorted the packets in wireshark in alphabetical order then looked for the first SMTP packet. The reason is that since we are investigating email evidence, the common protocols we should search for include IMAP, SMTP etc. In this case, the criminal used SMTP.

Next, there is a point where we highlight the stream index in the detailed section of the packet. This is because each stream refers to one email in this scenario and so the next TCP stream under the SMTP protocol would be the next email and so on. That is why when we found an SMTP packet with stream index=1, we then followed that TCP stream to see the complete message/conversation.

Below is a video of how the whole challenge was completed.

Comments

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Robsec

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