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Social engineering is an act of manipulating people to perform actions that they don’t intend to do. A cyber-based, socially engineered scenario is designed to trap a user into performing activities that can lead to the theft of confidential information or some malicious activity. The reason for the rapid growth of social engineering amongst hackers is that it is difficult to break the security of a platform, but it is far easier to trick the user of that platform into performing unintentional malicious activity. For example, it is difficult to break the security of Gmail in order to steal someone’s password, but it is easy to create a socially engineered scenario where the victim can be tricked to reveal his/her login information by sending a fake login/phishing page.

The Social-Engineer Toolkit is designed to perform such tricking activities. Just like we have exploits and vulnerabilities for existing software and operating systems, SET is a generic exploit of humans in order to break their own conscious security. It is an official toolkit available at https://www.trustedsec.com/, and it comes as a default installation with BackTrack 5. In this article, we will analyze the aspect of this tool and how it adds more power to the Metasploit framework. We will mainly focus on creating attack vectors and managing the configuration file, which is considered the heart of SET. So, let’s dive deeper into the world of social engineering.

Getting started with the Social-Engineer Toolkit (SET)

Let’s start our introductory recipe about SET, where we will be discussing SET on different platforms.

Getting ready

SET can be downloaded for different platforms from its official website: https://www.trustedsec.com/. It has both the GUI version, which runs through the browser, and the command-line version, which can be executed from the terminal. It comes pre-installed in BackTrack, which will be our platform for discussion in this article.

How to do it…

To launch SET on BackTrack, start the terminal window and pass the following path:

root@bt:~# cd /pentest/exploits/set root@bt:/pentest/exploits/set# ./set Copyright 2012, The Social-Engineer Toolkit (SET) All rights reserved. Select from the menu:

If you are using SET for the first time, you can update the toolkit to get the latest modules and fix known bugs. To start the updating process, we will pass the svn update command. Once the toolkit is updated, it is ready for use.

The GUI version of SET can be accessed by navigating to Applications | BackTrack | Exploitation tools | Social-Engineer Toolkit.

How it works…

SET is a Python-based automation tool that creates a menu-driven application for us. Faster execution and the versatility of Python make it the preferred language for developing modular tools, such as SET. It also makes it easy to integrate the toolkit with web servers. Any open source HTTP server can be used to access the browser version of SET. Apache is typically considered the preferable server while working with SET.

There’s more…

Sometimes, you may have an issue upgrading to the new release of SET in BackTrack 5 R3. Try out the following steps:

  1. You should remove the old SET using the following command:

    dpkg –r set

    We can remove SET in two ways. First, we can trace the path to /pentest/exploits/set, making sure we are in the directory and then opt for the ‘rm’ command for removing all files present there. Or, we can use the method shown previously.

  2. Then, for reinstallation, we can download its clone using the following command:

    Git clone https://github.com/trustedsec/social-engineer-toolkit /set

Working with the SET config file

In this recipe, we will take a close look at the SET config file, which contains default values for different parameters that are used by the toolkit. The default configuration works fine with most of the attacks, but there can be situations when you have to modify the settings according to the scenario and requirements. So, let’s see what configuration settings are available in the config file.

Getting ready

To launch the config file, move to the config file and open the set_config file:

root@bt:/pentest/exploits/set# nano config/set_config

The configuration file will be launched with some introductory statements, as shown in the following screenshot:

How to do it…

Let’s go through it step-by-step:

  1. First, we will see what configuration settings are available for us:

    # DEFINE THE PATH TO METASPLOIT HERE, FOR EXAMPLE /pentest/exploits/framework3 METASPLOIT_PATH=/pentest/exploits/framework3

    The first configuration setting is related to the Metasploit installation directory. Metasploit is required by SET for proper functioning, as it picks up payloads and exploits from the framework:

    # SPECIFY WHAT INTERFACE YOU WANT ETTERCAP TO LISTEN ON, IF NOTHING WILL DEFAULT # EXAMPLE: ETTERCAP_INTERFACE=wlan0 ETTERCAP_INTERFACE=eth0 # # ETTERCAP HOME DIRECTORY (NEEDED FOR DNS_SPOOF) ETTERCAP_PATH=/usr/share/ettercap Ettercap is a multipurpose sniffer for switched LAN. Ettercap section can be
    used to perform LAN attacks like DNS poisoning, spoofing etc. The above SET
    setting can be used to either set ettercap ON of OFF depending upon the
    usability. # SENDMAIL ON OR OFF FOR SPOOFING EMAIL ADDRESSES
    SENDMAIL=OFF

  2. The sendmail e-mail server is primarily used for e-mail spoofing. This attack will work only if the target’s e-mail server does not implement reverse lookup. By default, its value is set to OFF.

    The following setting shows one of the most widely used attack vectors of SET. This configuration will allow you to sign a malicious Java applet with your name or with any fake name, and then it can be used to perform a browser-based Java applet infection attack:

    # CREATE SELF-SIGNED JAVA APPLETS AND SPOOF PUBLISHER NOTE THIS REQUIRES YOU TO # INSTALL ---> JAVA 6 JDK, BT4 OR UBUNTU USERS: apt-get install openjdk-6-jdk # IF THIS IS NOT INSTALLED IT WILL NOT WORK. CAN ALSO DO apt-get install
    sun-java6-jdk
    SELF_SIGNED_APPLET=OFF

    We will discuss this attack vector in detail in a later recipe, that is, the Spear phishing attack vector . This attack vector will also require JDK to be installed on your system. Let’s set its value to ON, as we will be discussing this attack in detail:

    SELF_SIGNED_APPLET=ON # AUTODETECTION OF IP ADDRESS INTERFACE UTILIZING GOOGLE, SET THIS ON IF
    YOU WANT
    # SET TO AUTODETECT YOUR INTERFACE AUTO_DETECT=ON

  3. The AUTO_DETECT flag is used by SET to auto-discover the network settings. It will enable SET to detect your IP address if you are using NAT/Port forwarding, and it allows you to connect to the external Internet.

    The following setting is used to set up the Apache web server to perform web-based attack vectors. It is always preferred to set it to ON for better attack performance:

    # USE APACHE INSTEAD OF STANDARD PYTHON WEB SERVERS, THIS WILL INCREASE SPEED OF # THE ATTACK VECTOR APACHE_SERVER=OFF # # PATH TO THE APACHE WEBROOT APACHE_DIRECTORY=/var/www

  4. The following setting is used to set up the SSL certificate while performing web attacks. Several bugs and issues have been reported for the WEBATTACK_SSL setting of SET. So, it is recommended to keep this flag OFF:

    # TURN ON SSL CERTIFICATES FOR SET SECURE COMMUNICATIONS THROUGH
    WEB_ATTACK VECTOR
    WEBATTACK_SSL=OFF

  5. The following setting can be used to build a self-signed certificate for web attacks, but there will be a warning message saying Untrusted certificate. Hence, it is recommended to use this option wisely to avoid alerting the target user:

    # PATH TO THE PEM FILE TO UTILIZE CERTIFICATES WITH THE
    WEB ATTACK VECTOR (REQUIRED)
    # YOU CAN CREATE YOUR OWN UTILIZING SET, JUST TURN ON SELF_SIGNED_CERT # IF YOUR USING THIS FLAG, ENSURE OPENSSL IS INSTALLED! # SELF_SIGNED_CERT=OFF

  6. The following setting is used to enable or disable the Metasploit listener once the attack is executed:

    # DISABLES AUTOMATIC LISTENER - TURN THIS OFF IF YOU DON'T WANT A
    METASPLOIT LISTENER IN THE BACKGROUND.
    AUTOMATIC_LISTENER=ON

  7. The following configuration will allow you to use SET as a standalone toolkit without using Metasploit functionalities, but it is always recommended to use Metasploit along with SET in order to increase the penetration testing performance:

    # THIS WILL DISABLE THE FUNCTIONALITY IF METASPLOIT IS NOT INSTALLED AND
    YOU JUST WANT TO USE SETOOLKIT OR RATTE FOR PAYLOADS
    # OR THE OTHER ATTACK VECTORS. METASPLOIT_MODE=ON

These are a few important configuration settings available for SET. Proper knowledge of the config file is essential to gain full control over the SET.

How it works…

The SET config file is the heart of the toolkit, as it contains the default values that SET will pick while performing various attack vectors. A misconfigured SET file can lead to errors during the operation, so it is essential to understand the details defined in the config file in order to get the best results. The How to do it… section clearly reflects the ease with which we can understand and manage the config file.

Working with the spear-phishing attack vector

A spear-phishing attack vector is an e-mail attack scenario that is used to send malicious mails to target/specific user(s). In order to spoof your own e-mail address, you will require a sendmail server. Change the config setting to SENDMAIL=ON. If you do not have sendmail installed on your machine, then it can be downloaded by entering the following command:

root@bt:~# apt-get install sendmail Reading package lists... Done

Getting ready

Before we move ahead with a phishing attack, it is imperative for us to know how the e-mail system works.

Recipient e-mail servers, in order to mitigate these types of attacks, deploy gray-listing, SPF records validation, RBL verification, and content verification. These verification processes ensure that a particular e-mail arrived from the same e-mail server as its domain. For example, if a spoofed e-mail address, , arrives from the IP 202.145.34.23, it will be marked as malicious, as this IP address does not belong to Gmail. Hence, in order to bypass these security measures, the attacker should ensure that the server IP is not present in the RBL/SURL list. As the spear-phishing attack relies heavily on user perception, the attacker should conduct a recon of the content that is being sent and should ensure that the content looks as legitimate as possible.

Spear-phishing attacks are of two types—web-based content and payload-based content.

How to do it…

The spear-phishing module has three different attack vectors at our disposal:

Let’s analyze each of them.

Passing the first option will start our mass-mailing attack. The attack vector starts with selecting a payload. You can select any vulnerability from the list of available Metasploit exploit modules. Then, we will be prompted to select a handler that can connect back to the attacker. The options will include setting the vnc server or executing the payload and starting the command line, and so on.

The next few steps will be starting the sendmail server, setting a template for a malicious file format, and selecting a single or mass-mail attack:

Finally, you will be prompted to either choose a known mail service, such as Gmail or Yahoo, or use your own server:

1. Use a gmail Account for your email attack. 2. Use your own server or open relay set:phishing>1 set:phishing> From address (ex: moo@example.com):bigmoney@gmail.com set:phishing> Flag this message/s as high priority? [yes|no]:y

Setting up your own server cannot be very reliable, as most of the mail services follow a reverse lookup to make sure that the e-mail has generated from the same domain name as the address name.

Let’s analyze another attack vector of spear-fishing. Creating a file format payload is another attack vector in which we can generate a file format with a known vulnerability and send it via e-mail to attack our target. It is preferred to use MS Word-based vulnerabilities, as they are difficult to detect whether they are malicious or not, so they can be sent as an attachment via an e-mail:

set:phishing> Setup a listener [yes|no]:y [-] *** [-] * WARNING: Database support has been disabled [-] ***

At last, we will be prompted on whether we want to set up a listener or not. The Metasploit listener will begin and we will wait for the user to open the malicious file and connect back to the attacking system.

The success of e-mail attacks depends on the e-mail client that we are targeting. So, a proper analysis of this attack vector is essential.

How it works…

As discussed earlier, the spear-phishing attack vector is a social engineering attack vector that targets specific users. An e-mail is sent from the attacking machine to the target user(s). The e-mail will contain a malicious attachment, which will exploit a known vulnerability on the target machine and provide a shell connectivity to the attacker. The SET automates the entire process. The major role that social engineering plays here is setting up a scenario that looks completely legitimate to the target, fooling the target into downloading the malicious file and executing it.


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