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Welcome to Mark Baggett - In Depth Defense

I am the course Author of SANS SEC573 Automating Information Security with Python. Check back frequently for updated tools and articles related to course material.




Don't forget to wipe!

A while back I assisted the FBI in the collection of evidence of a now convicted sexual offender. The guy had a hard drive full of child porn. My customer had suspicions that an employee in a remote office was accessing inappropriate material on their work computer and asked that I investigate it remotely. After finding one photo of a very young girl among a collection of "normal" porn and discussing it with my customer, I immediately dial my contact with the FBI. (Good contacts are ESSENTIAL don't wait until you need them to try and make them.) Although the young girl was clothed in the picture I saw, the lingerie and pose she was in was very disturbing and you just knew you didn't want to see anything else. At that point I froze; anything else that was touched remotely was altering and potentially destroying evidence on the remote drive. Within an hour the FBI was at the office. He used my machine and the access I had gained to briefly verify the contents of the drive and confirm that it required additional investigation. It did and they dispatched local agents to grab the drive for proper forensic collection.

I spared myself the imagery and let the FBI do what it needed to do using my machine. To me, this story is very interesting. Here a person in a very similar role as the one I played. He could be prosecuted for any residual images left behind on his drive after an investigation.

http://www.theregister.co.uk/2009/05/22/bates_hard_drives/

As far as I know, no CP was ever copied to my hard drive. I had donated a thumbdrive to the cause where all the evidence they needed during that brief investigation was collected. If it is a project I am working on with sensitive data (such as a penetration test) I like to keep everything in TrueCrypt volume making clean up very easy. But in this case, I wasn't driving. It was a windows box and I periodically run "CIPHER /W:C:\" to clean up all the residual files in the free space on the drive, but it’s not something I do religiously. How about you? Well, Cipher is running NOW!

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https://github.com/MarkBaggett/srum-dump/tree/python3

In moving to Python3 I also updated the modules that I depend upon to parse and create XLSX files and access the ESE database that contains the SRUM data.  I hope that this will fix the issue that some users have experienced with SRUDB.dat files that create very large spreadsheets.  If it does not please let me know and continue to use SRUM_DUMP_CSV.EXE to avoid the XLSX problem.

In moving to Python3 you will find the process to be faster.

If you would like to run the tools from source instructions for doing so are in the README on the github page.

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I read an article on Fireeye's website the other day where they used Machine Learning to eliminate a lot of the noise that comes out of tools like strings.  It's pretty interesting and looks like it would save me some time when looking through malware.

https://www.fireeye.com/blog/threat-research/2019/05/learning-to-rank-strings-output-for-speedier-malware-analysis.html

I wondered how effective freq.py scores would be in helping to eliminate the noise.  45 minutes and 29 lines of Python code later I have something that looks like it works.  Check out freq_sort.py.

Before freq_sort.py here is the output of strings on a piece of malware:

student@573:~/freq$ strings -n 6 malware.exe | head -n 20
!This program cannot be run in DOS mode.
e!Rich
`.rdata
@.data
.pdata
@.gfids
@.rsrc
@.reloc
\$0u"H
L$ SVWH
K SVWH
|$ H;_
<bt%<xt!<Zt
|$ AVH
l$ VWAV
L$ SUVWH
UVWATAUAVAWH
0A_A^A]A\_^]
UVWATAUAVAWH
@A_A^A]A\_^]

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Windows TCPDUMP without installing WINPCAP!!!!!!!!

IMHO, This is a long time coming for Windows. I love this thing. You probably already know about it, but I haven't read much about it anywhere and Its been very useful to me. Its a version of tcpdump for windows that doesn't require I install the Winpcap drivers. I use it along with PSEXEC to start remote sniffing probes on Windows workstations. I'm sure its NOT forensically sound to do this in on a box that may contain evidence because of the swap file, but for information gathering something like this is very useful.

So with this..
http://www.microolap.com/downloads/tcpdump/tcpdump.zip

Something like this

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Lets me turn every node on my network into a remote Snort probe, or just capture anamolies!