Div0 Blog Editor
Thug – A Client Honeypot
Updated: May 23, 2020
Introduction to Thug & Client Honeypot
Client honeypots are amazing tools for security practitioners who wish to perform a quick analysis of Websites, communication channels, etc.
I was previously fascinated by Capture-HPC – a high-interaction client honeypot – developed by Christian Seifert & Ramon Steenson from The Honeynet Project, New Zealand Chapter. The project was later adopted and extended by The HoneySpider Network (HSN) – the HSN Capture-HPC NG. However, a high-interaction client honeypot may be a little much if I just want to perform a simple/light-weight analysis.
Thug is a Python low-interaction client honeypot publicly released in March 2012 by Angelo Dell’Aera at the Honeynet Project Security Workshop, held at Facebook Inc., Menlo Park.
This write-up demonstrates how to you can get Thug running on your (Linux) machine, and how it can be used to perform analysis on sites of your interest.
Getting Started with Thug
I setup Thug on my Ubuntu 12.04.4 LTS machine.
Python 2.7 is required to run Thug properly
apt-get install python2.7 python2.7-dev
apt-get install git cd /opt/ git clone git://github.com/buffer/thug.git
Install Google V8 & PyV8
sudo apt-get install subversion cd /opt/ svn checkout http://v8.googlecode.com/svn/trunk/ v8 svn checkout http://pyv8.googlecode.com/svn/trunk/ pyv8 cp thug/patches/PyV8-patch* . patch –p0 < PyV8-patch1.diff sudo apt-get install build-essential libboost-python-dev export V8_HOME=/opt/v8 cd /opt/pyv8 python setup.py build sudo python setup.py install
If you faced problem with LibBoost, checkout StackOverFlow Question #7160608.
Install Beautiful Soup 4
apt-get install python-setuptools easy_install beautifulsoup4
sudo apt-get install autoconf libtool cd /tmp/ git clone git://git.carnivore.it/libemu.git cd libemu autoreconf –v –i ./configure --prefix=/opt/libemu sudo make install
cd /opt/ git clone git://github.com/buffer/pylibemu.git cd pylibemu python setup.py build sudo python setup.py install
Install Zope Interface
apt-get install python-pip pip install python-magic
Install Yara & Yara-Python
apt-get install libpcre3 libpcre3-dev cd /opt/ git clone git://github.com/plusvic/yara.git cd yara ./build.sh sudo make install cd yara-python python setup.py build sudo python setup.py install echo “/usr/local/lib” >> /etc/ld.so.conf ldconfig
apt-get install mongodb
Test if Thug works
python /opt/thug/src/thug.py –h
If you get “ImportError: libemu.so.2: cannot open shared object file: No such file or directory” error:
touch /etc/ld.so.conf.d/libemu.conf echo “/opt/libemu/lib/” > /etc/ld.so.conf.d/libemu.conf ldconfig
Here are some flags that you should be familiar with:
-u flag – using different browser personalities / user-agents plus supported schemes
-r flag – specifying a referrer
-l flag – analysing a local HTML file
-o flag – logging to a specified file
-v flag – enabling verbose mode
Analysing Something Simple
The European Union Agency for Network & Information Security (ENISA) has a series of Computer Emergency Response Team (CERT) Exercise & Training Material – containing Handbook, Toolset and Virtual Image – to support hands-on training sessions essential for success in the CERT community and in the field of information security.
Amongst all, ENISA has an exercise specifically on honeypots; with the objective to familiarise users with server- and client-honeypots: Honeypots CERT Exercise Handbook / Toolset / Virtual Image
In this and the next section, I will be referencing to the CERT Exercise Handbook and utilising the Virtual Image supplied by ENISA for my demo.
Since I already have Thug installed on my Ubuntu 12.04.4 LTS machine, I will only be using the Virtual Image as a Web Server to serve me a suspicious Website.
1st, fire up the Apache service. The username and password of the Virtual Machine is “student”, and “honeypot” respectively.
Next, configure the /etc/ hosts file of your Thug machine such that you can access the Website via a suspicious URL
Analysing Suspicious Webpage (ex1.html) Using Thug
With the network all set, let the analysis begin!
Here we see 3 interesting activities:
An [iFrame Redirection] on ex1.html to ex2.html;
Another [iFrame Redirection] to ex3.html; and
An [Window] alert text with “you are using Internet Explorer not 7”
Thug also captured the HTML source code of the 3 Webpages (ex1.html, ex2.html & ex3.html) it visited during the analysis; located at /opt/thug/logs, each Webpage is named after its MD5 hash value.
Since Thug emulates the personality of Internet Explorer 6.1 on Windows XP by default, an iFrame redirection to ex3.html was displayed during the analysis.
Is ex1.html Malicious?
Analysing Something Malicious
Continuing from where we left off, we know that there are two other outcomes (i.e. malicious.html & ex4.html) depending on the user agent used to access ex2.html.
We know that we’ll be served with malicious.html via the iFrame if we are using an Internet Explorer 7 personality, and ex4.html for any other non-IE personality.
So let’s begin with the former!
Redirection to malicious.html
Using Thug, repeat the analysis process using an Internet Explorer 7 personality.
Here we see a much more interesting events going on:
An [iFrame Redirection] on ex1.html to ex2.html;
Another [iFrame Redirection] to malicious.html;
At malicious.html, an ActiveX object is created, and it uses some functions to fetch a file – malware.exe – and writes it to visitors’ C drive as sysqvda.exe.
In addition to the 3 Webpages (ex1.html, ex2.html & malicious.html) Thug has analysed, it saved a copy of sysqvda.exe (i.e. malware.exe) in the analysis log directory – /opt/thug/logs. Such files can be analysed using external tools or services (e.g. VirusTotal, Anubis, Cuckoo, etc.).
Upon analysing the captured suspicious binary, you will find that it’s just an EICAR test file.
Is ex1.html Malicious?
It is considered as malicious when you are browsing it with an Internet Explorer 7 Web browser. Although it’s just an EICAR test file, it’s considered as a “malware”.
What about ex4.html?
We’ve analysed ex3.html & malicious.html. What about ex4.html which ex2.html’s iFrame which may have redirected us to?
Now perform an analysis using any other user agent other than that of an Internet Explorer. I used Firefox 12 on a Windows XP machine.
Now it’s your turn to perform your own analysis.
Practice Makes Perfect!
You should be familiar with Thug. The Virtual Image provided by ENISA offers another suspicious Website you can practice your analysis skills on.
Using the same network setup:
This case is no longer contained within a single URL; therefore, you will have to update your /etc/ hosts file on your analysis machine (my Ubuntu 12.04.4 LTS machine) to the following:
Now begin your analysis of http://www.coruscant.emp/main.html!
Ask yourself the following questions (Source: ENISA’s Honeypots CERT Exercise Handbook):
Is the web site malicious or not?
How was the attack carried out? Describe step by step (could be presented as a flow diagram).
What domain names and IP addresses are involved in the attack?
Which browsers are targeted?
Which vulnerabilities are exploited and how?
How could we mitigate the attack?
Know Your Enemy: Behind the Scenes of Malicious Web Servers – Obfuscation
Emil Tan, Chapter Lead, The Honeynet Project, Singapore Chapter