Puzzle #4: The Curious Mr. X

While a fugitive in Mexico, Mr. X remotely infiltrates the Arctic Nuclear Fusion Research Facility’s (ANFRF) lab subnet over the Interwebs. Virtually inside the facility (pivoting through a compromised system), he conducts some noisy network reconnaissance. Sadly, Mr. X is not yet very stealthy.

Unfortunately for Mr. X, the lab’s network is instrumented to capture all traffic (with full content). His activities are discovered and analyzed… by you!

Here is the packet capture containing Mr. X’s activity. As the network forensic investigator, your mission is to answer the following questions:

1. What was the IP address of Mr. X’s scanner?
2. For the FIRST port scan that Mr. X conducted, what type of port scan was it? (Note: the scan consisted of many thousands of packets.) Pick one:

  • UDP
  • TCP Connect

3. What were the IP addresses of the targets Mr. X discovered?
4. What was the MAC address of the Apple system he found?
5. What was the IP address of the Windows system he found?
6. What TCP ports were open on the Windows system? (Please list the decimal numbers from lowest to highest.)
X-TRA CREDIT (You don’t have to answer this, but you get super bonus points if you do): What was the name of the tool Mr. X used to port scan? How can you tell? Can you reconstruct the output from the tool, roughly the way Mr. X would have seen it?

Deadline is 3/18/10 (11:59:59PM UTC-11) (In other words, if it’s still 3/18/10 anywhere in the world, you can submit your entry.)

Please use the Official Submission form to submit your answers. Here is your evidence file:
MD5 (evidence04.pcap) = 804648497410b18d9a7cb1d4b2252ef7

The MOST ELEGANT solution wins. In the event of a tie, the entry submitted first will receive the prize. Coding is always encouraged. We love to see well-written, easy-to-use tools which automate even small sections of the evidence recovery. Graphical and command-line tools are all eligible. You are welcome to build upon the work of others, as long as their work has been released under a an approved Open Source License. All responses should be submitted as plain text. Microsoft Word documents, PDFs, etc will NOT be reviewed.

Feel free to collaborate with other people and discuss ideas back and forth. You can even submit as a team (there will be only one prize). However, please do not publish the answers before the deadline, or you (and your team) will be automatically disqualified. Also, please understand that the contest materials are copyrighted and that we’re offering them publicly for the community to enjoy. You are welcome to publish full solutions after the deadline, but please use proper attributions and link back. If you are interested in using the contest materials for other purposes, just ask first.

Exceptional solutions may be incorporated into the SANS Network Forensics Investigative Toolkit (SNIFT kit). Authors agree that their code submissions will be freely published under the GPL license, in order to further the state of network forensics knowledge. Exceptional submissions may also be used as examples and tools in the Network Forensics course. All authors will receive full credit for their work.

Deadline is 3/18/10 (11:59:59PM UTC-11). Here’s the Official Submission form. Good luck!!

Copyright 2010, Lake Missoula Group, LLC. All rights reserved.


  1. Is it worth submitting a solution that uses a MANUAL search of the PCAP file with Wireshark? Or do we have to automate the process?

  2. Tim — Yes, definitely! We encourage people to submit all kinds of solutions, and we publish the names of everyone who gets the correct answer, regardless of how you achieved it. If you’re competing for the prize, you will need to create an automated solution of some kind. That said, we love reading well-thought-out writeups of manual analysis, and we encourage you to post your methods on your blogs (after the deadline, of course).

    There is a lot to be learned from manual analysis.

  3. You’ve ruined my plan to use the time between your contests to work on this year’s Underhanded C contest! I was counting on at least a month between contests! You spoil us!

  4. Sherri, how about the prizes??? 🙂

    SANS conference tickets?

  5. Any idea yet about the prize?

  6. Hi guys,

    The most important part! We’ll be announcing the prize early next week 🙂


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