Author: kanishka10

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Beginners guide to Eyewitness tool

Hello aspiring ethical hackers. In our previous blogpost, you studied about website footprinting. In this blogpost, you will learn about a tool called eyewitness which helps you to decide which website to focus on.

In ethical hacking, before trying to footprint a website, it would be good if we have a general idea about what websites to target first. For example, a company you are going to pen test may have multiple websites and sub domains. Before we jump into password cracking or exploitation or directory busting or perform any other attack, it would be good if we are first able to decide what website and URLs to target first. The role of eyewitness tool comes there. Eyewitness takes the screenshots of the URLs or websites you provide. Apart from taking screenshot of the URL, it will also capture any header info and default passwords.

Let’s see how to use this tool. For this we will be using Kali Linux as this tool is available by default in Kali repositories. As target, we will be using Metasploitable 2 installed in our virtual hacking Lab. It can be installed as shown below.

Target a single URL (–single)

You can take screenshot of a single URL as shown below.

As soon as it writes a report for your target, it will ask you if you want to open the report. Click on “Yes”. It will open the report as shown below.

You can even view the code of the URL you scanned.

But the real power of eyewitness can be seen when we are targeting multiple URLs at once. For doing this, we will first create a file called URLS.txt and add some URLs we want to target as shown below.

Target multiple URLs (-f)

Multiple URLs can be targeted with this tool by specifying the above created file with (-f) option.

Here’s the report.

One of our URLs we targeted ended up in a error.

Skip DNS resolution(–no-dns)

In some cases, while using eyewitness tool, you may have to go through a VPN. In such cases, it is good to skip DNS resolution when connecting to the website. This option helps you to do it.

Resolve IP / host name for your target (–resolve)

Time to wait while requesting an URL (–timeout)

By default, eyewitness waits for 7 seconds before it goes to take a screenshot of a new webpage. However, this can be changed with this option. For example, let’s change the timeout time to 1 second.

Add jitter (–jitter)

Using this option, we can randomize the URLs specified and add a random delay.

Add delay before taking a screenshot (–delay)

Using the option, we can add delay between opening of the navigator and taking a screenshot. This delay can be specified in seconds. For example, let’s add 10 seconds delay before taking screenshot.

Maximum retries (–max-retries)

This option specifies eyewitness tool how many retries it has to make if it fails to grab a screenshot on the first attempt.

Specify directory name for saving the report (-d)

This option is used to specify a directory name for saving the report.

Number of results to show on one page (–results)

By default, eyewitness shows output for all the URLs given as input on a single page. This option can be used to specify how many results to show per page. For example, let’s set it to show 1 result per page.

As you can see, now, all the results are shown on separate pages.

You don’t want to be prompted for viewing the report (–no-prompt)

If you don’t want eyewitness to prompt you to open the report after finishing its work, you can use this option.

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How to create a payload

Hello, aspiring ethical hackers. In this blogpost, you will learn what is a payload and how to create a payload manually. Note that it is only for educational and knowledge purposes and not for performing any malicious actions. The aim of this article is to give you a basic understanding on how to create a payload. Let’s start with defining what exactly is a payload.

What is a payload?

A payload in cyber security is a piece of code that is executed after successfully running an exploit to take advantage of a vulnerability. When a Proof Of Concept (POC) for a vulnerability is disclosed, this allows most hackers around the world to execute their chosen payloads. This payload can be anything from malware, reverse shell, RAT, ransomware etc or their own custom payload.

For example, ms08_067 vulnerability was exploited in real-world to deploy Conficker worm payload, but while pen testing with Metasploit, meterpreter is used as payload. Although payloads can be created using payload generators simply, it would be very thrilling and educative to create manually.

Creation of a computer payload consists of six steps. They are,

  1. Decide the function you want your payload to perform.
  2. Select a programming language in which you want to code your payload.
  3. Code the payload.
  4. Compiling the payload.
  5. Testing.
  6. Sharing the payload.

Let’s learn about each step in detail.

1. Function of a payload:

Before you even start coding a payload, you need to decide what exactly you want your payload to do. In real-world, payloads perform many functions that include downloading and installing additional payloads, wiping data from the infected system and even taking complete control of the system. For example, I decide that my payload should open a Firefox browser when executed.

2. Choose your language:

After deciding the function you want your payload to perform, next thing you have to do is choose a programming language to code this payload. Payloads can be written in many programming languages like C, Delphi, Visual Basic, C#, C++, Cobol, Ruby, Python etc. They can also be created using scripting languages like JavaScript, Batch script, Bash, PowerShell etc. Choose the programming or scripting language of your choice. For example, I want to write my payload in Batch scripting.

3. Write code:

Once you select the programming language or scripting language, you need to code the payload. To code a batch script, all I have to do is open a notepad, add the code shown below and save the file as Batch file (with extension .bat)

@echo off
start firefox.exe

4. Compile (if necessary):

Compile the payload. Compiling is a process of converting source code into machine-readable code so that a computer can execute it. Since we have written our code in Batch, it doesn’t need any compilation. But programs written in C,C++, Python need compiling. Compiled programs are usually fast.

5. Test the payload:

Once you have finished coding the virus and compiling it, test its working by executing the virus. I execute the Batch virus I created and it open Firefox browser as shown below.

6. Share the virus:

The last step is to share the payload to make your target user execute it. Normally hackers use social engineering or phishing schemes to spread the paylaod.

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Beginners guide to MAC flooding

Hello, aspiring ethical hackers. In our previous blogpost on data link layer attacks, you learnt what is a hub, What is a switch, how they both work, what is a MAC address, what is a CAM table and different types of LAN attacks etc. In this blogpost, you will learn about one such attack, MAC flooding attack.

What is MAC flooding?

MAC flooding attack is an attack on the network switch that floods the network switch with fake MAC addresses. The purpose of this attack is to consume memory of the network switch. Once the CAM table of the network switch becomes full, the MAC addresses of the legitimate devices are purged out of the CAM table.

The network switch can no longer save new MAC addresses sent to the switch and it soon falls into a fail-open mode in which it will broadcast the incoming data to all the ports of the switch instead of transferring it to the intended device. Typically, the switch here functions like a network hub.

Since the data is now being broadcast to all the devices connected to the network, hackers can sniff on data belonging to all the devices in the network.

There are many ways to perform MAC flooding. One such method is to using a too named macof. Macof is a tool that comes with dsniff package. macof is used to flood the local network with random MAC addresses. It is installed by default in Kali Linux. The default way to flood the switch with macof is to specify the interface as shown below. 

sudo macof -i eth0

This will create multiple random MAC addresses. You can even specify the number of packets you want to create as shown below.

sudo macof -i <interface> -n <number of packets to create>

You can even specify the source IP address from where these random MAC address should originate from.

sudo macof -i <interface> -s <IP address> -n <number of packets to create>

You can also specify the MAC address or physical address of the target device you want to flood with random MAC addresses. 

sudo macof -i <interface> -e <Physical address of target>
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Beginners guide to dirbuster

Hello, aspiring ethical hackers. In this blogpost, you will learn about dirbuster, a tool used to scan web directories and file names on web application servers. Dirbuster is written in Java and can be installed on Linux systems. Almost all pentesting distros include this in their tools list. For this tutorial, we are going to use Kali Linux. Dirbuster can be started on Kali by using the command as shown below.

dirbuster

Typing this command will open a GUI window as shown below.

Here, you can configure all the options required to scan the target web server. For this tutorial, we will be using Metasploitable 2 as our target. Any directory scanning and fuzzing tool is as good as the wordlist it uses while scanning for hidden directories and files. Dirbuster provides its own set of wordlists which are located in “usr/share/dirbuster/wordlists” directory in Kali.

Unlike other wordlists, these wordlists are created using a different approach. These lists are created from scratch by crawling the internet and making a collection of the all the files used by all developers. It comes with a total of 9 different lists. If all these lists fail, dirbuster also has brute force option.

The scan starts. Depending on the size of the target web server, finishing time may vary. The progress of the scan will be displayed in the “scan information” tab.

As the scan continues, you can see the results in different views. The “List view” shows all the detected directories and files by dirbuster in the form of a list.

You can also see the results of the scan in the form of “Tree view” that enables us to gain understanding about the target web server directories structure.

You can right click on the detected directories for more options as shown below.

If dirbuster faces any errors while scanning directories, they are displayed in the “errors” tab.

You can wait until the scan finishes or you can even end the scan by hitting “stop” button. Once you do that, dirbuster will prompt you to save the result of the scan as shown below.

You can also use dirbuster by specifying its options through command line. The basic options to set are the URL and the wordlist. These can be set with ‘-U’ and ‘-r’ options respectively.

Then, all you have to do is click on “Start”. If you want to find files with a particular extension with dirbuster the option is ‘-e’. For example, let’s say you want it scan for files with “php” extension here is the command,

To save the output of dirbuster scan, use command line option ‘-r’.

Headless mode (-H)

You can run dirbuster in headless mode without GUI option as shown below.

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Aircrack-ng: Complete guide to beginners

Hello, aspiring ethical hackers. In our previous blogpost, you learnt what is Wifi hacking and different techniques to hack wireless networks. In most of these hacking techniques, a tool named aircrack plays a very important role.

In this blogpost, you will learn about this tool. Aircrack-ng or aircrack ng is a complete suite of tools used to test wi-fi network security. The various functions of aircrack include,

  1. Monitoring: It can be used to capture wireless packets and save data in text file which can be processes by third party tools.
  2. Attacking: We can use it too perform various wireless attack like Replay attacks, DE authentication access points and other attacks.
  3. Testing: Checking Wi-Fi cards and capability of the drivers. (capture and injection)
  4. Cracking: For cracking WEF and WPA PSK (WPA 1 and WPA 1) passwords.

Just now, we have learnt that aircrack-ng is a combination of tools. Let’s understand what those tools are and what are they used for.

1. airbase-ng:

It is a multi purpose tool that can be used to attack the Wi Fi client instead of the Wi Fi access point.

2. airdecap-ng:

With this tool, you can decrypt WEP/WPA/WPA2 capture files. It is also used to remove the wireless headers from an unencrypted wireless capture.

3. aircrack-ng:

It is key cracking program.

4. airdecloak-ng:

Some wireless Intrusion Prevention System (WIPS) prevent WEP from being cracked by using fake WEP frames. This tool removes the WEP cloaking frame a captured pcap file.

5. airdrop-ng:

airdrop-ng is a program used to de authenticate users from access points. It uses rule based de authentication techniques that can be MAC address, type of hardware, etc.

4. aireplay-ng:

This tool is used to inject frames. It is used to generate traffic which can be used later by aircrack-ng for WEP and WPA-PSK key cracking.

5. airmon-ng:

It is used to enable monitor mode on wireless interfaces.

6. airodump-ng:

This tool is used to capture raw 802.11 packets. It is used particularly for collecting WEP IVS or WPA handshakes to crack later with aircrack.

7. airolib-ng:

This is a tool designed to store and manage ESSID and password lists. calculate their Pairwise Master Keys (PMK’s) and use them in WPA/WPA2 cracking.

8. airtun-ng:

This tool creates a virtual tunnel interface. It has two basic functions. They are, allowing all encrypted traffic to be monitored for wireless interface detection system (WIDS) and injecting arbitrary traffic into a network.

9. Besside-ng:

It is used to automatically crack WEP and WPA networks . See how to automatically crack WEP and WPA networks with Besside. Learn more about it .

10. dcrack-ng:

dcrack is used to distribute WPA2 / PSK cracking process across multiple servers.

11. easside-ng:

This tool is a magic tool that allows you to communicate with a WEP access point without knowing its WEP key.

12. packetforge-ng:

This tool is used to create encrypted packets to be used for packet injection. Using this tool, we can create various types of packets like ARP requests, UDP, ICMP and custom packets.

13. tkiptun-ng:

This tool is used to inject a few frames into a WPA TKIP network.

14. wesside-ng:

Wesside-ng is another auto-magic tool that uses a variety of techniques to get the WEP key.

    Cracking WEP passwords with aircrack

    Let’s see how to crack WEP passwords with aircrack. All wifi hacking attacks require a wireless adapter that supports packet injection. For this tutorial, I am using ALFA Wireless USB adapter. My attacker machine is Kali Linux which is installed on VMware. So I first connected the ALFA wireless adapter to my laptop and make sure it is connected to the Kali Linux virtual machine. Now, I open a terminal in Kali Linux and type command shown below that shows all the wireless interfaces connected to the machine. 

    iwconfig

    Then I start monitor mode on the wireless interface. Monitor mode is just like promiscuous mode on wired interfaces. When in monitor mode, the wireless adapter sniffs on all the wireless traffic around.

    I once again run the “iwconfig” command to have a look at the wireless interfaces to confirm monitor mode started on the Wireless interface.

    As you can see the name of the wireless interface changed from waln0 to wlan0mon. The monitor mode is on. To see all the traffic being observed by the wireless interface, I run the command airodump-ng on the wireless interface.

    how to crack wep with aircarck

    As you can see, this shows all the wireless traffic around us. There are many wireless networks available but my target is the Wi-Fi Access point I named “Hack_Me_If_You_Can”. I use the same airodump-ng to target the MAC address of target’s Access point and route all the traffic it has to a file named wep_hc_crack.

    In the above image, you can see the clients connected to the targeted Wi-Fi Access point. All the traffic belonging to the Wi-Fi access point “Hack_Me_If_You_Can” will be saved in the file “wep_hc_crack.cap”. What I am looking for is the initialization vectors that are useful in cracking WEP. This initialization vectors play a key role in cracking the password of any WEP enabled Wi-Fi access point.

    Just remember the more IV’s we have, the more the chances of cracking the WEP password. Since I need more traffic to crack the WEP password fast, I can use some tricks to create more traffic. A feature of aircrack-ng, aireplay-ng helps us to create more traffic. It has various methods of creating additional traffic. One such method is ARP request replay attack.

    The classic ARP request replay attack is the most effective way to generate new initialization vectors (IVs), and works very reliably. The program listens for an ARP packet then retransmits it back to the access point. This, in turn, causes the access point to repeat the ARP packet with a ne- w IV. The program retransmits the same ARP packet over and over. However, each ARP packet repeated by the access point has a new IVs. It is all these new IVs which allow you to determine the WEP key. This attack can be started as shown below.

    where “-h” option is used to specify the MAC address of any client we want to use. Here is another way in which you can start the ARP replay attack.

    As initialization vectors start collecting in the wep_hc_crack file, I can use aircrack to try cracking the password. The command is “aircrack-ng wep_hc_crack.cap“.

    If the initialization vectors are too less (in this case I have a new 20) aircrack wait for enough initialization vectors. I continue the ARP request replay attack until traffic increases.

    You can see the traffic increasing. All have to do is play the game of patience now .

    After collecting almost 25000 IV’s aircrack finally cracked the WEP password. The password of the Wi-Fi access point is 1234567899. It’s a 64bit hexadecimal key. As you can see, it took me around one hour thirty five minutes for me to crack the password.

    Cracking WPA / WPA2 passwords with aircrack

    Now, let’s see how to crack WPA / WPA2 with aircrack. WPA stands for Wifi Protected Access. It is an encryption system to secure WLAN networks. It eliminates all known vulnerabilities in WEP(Wired Equivalent Privacy).  WPA uses 128 bit key and  48 bit initialization vector while WEP uses 108 bit key with 24 bit initialization vector. WPA2 is the successor of WPA. Both WPA and WPA2 use temporal key integrity protocol(TKIP) for encryption and  pre-shared key(PSK) authentication.  The only difference between WPA and WPA2 is that they use Rivest Cipher(RC4) and Advanced Encryption Standard(AES) encryption algorithms respectively. Both can be configured to use counter cipher block chaining mode(CCM) though. They are by far considered  most secure for Wifi networks.

    I am using the same arrangement I used for cracking WEP above. So let’s start. Once you have booted into Kali Linux, open terminal and type command “iwconfig”. It lists your wireless interfaces just like ifconfig shows wired interfaces.

    We can see that we have a wireless interface wlan0. Now we are going to start monitor mode on our wireless interface. Monitor mode is same as promiscuous mode in wired sniffing. Type command shown below. We can see below that monitor mode has been enabled on “mon0″.

    airmon-ng start wlan0

    Now let’s see all the traffic collected by our wireless interface. Type command airodump-ng mon0.

    Hit Enter. We can see all the wireless networks available as shown below.

    crack wpa

    We can see that all the wifi networks are configured with  WPA2 or WPA. We are going to hack the network “shunya”. We will collect the shunya’s network traffic into a file. Open a terminal and type command “airodump-ng –bssid <Mac address of wifi access point> -c 13 –write wpacrack mon0″.

    where

    • –bssid stands for base station security identifier
    • <MAC address> is the Mac address of access point.
    • -c is used to specify the channel the wifi network is operating on.
    • –write to write to a file.
    • “wpacrack”  is the file name we are writing into.
    • mon0 is the interface.

    Hit Enter. We will see the result as below.

    We can only hack a WPA/WPA2 protected Wifi network by capturing its handshake process or association( when the client is trying to connect to the wifi network.).  So let’s try to disconnect all the clients connected to the wireless network “shunya” first. Open a new terminal and type the command 

    aireplay-ng –deauth 100 -a <MAC> –ignore-negative-one mon0

    where

    –deauth are the de authentication packets,

    100 are the number of de authentication packets we want to send.

    -a stands for access point.

    <MAC> is the MAC address of the wireless access point.

    This command will send 100 de authentication packets to the broadcast address of the wireless access point. This will make all the clients connected to the “shunya” get disconnected. As soon as this happens, all the clients will try to connect back to the wireless network once again. We can see that a WPA handshake has happened in the previous terminal.

    Now let’s see where our capture file is located. Type “ls”. We will do dictionary password cracking here. So let’s find out where the dictionaries are.  Type command “locate wordlists”. This will show us a number of wordlists available by default in Kali Linux.

    Our captured traffic is stored in .cap file. We will use the wordlist big.txt for cracking the password. Open a new terminal and type command 

    aircrack-ng wpacrack-01.cap -w /usr/share/dirb/wordlists/big.txt

    Hit Enter. If our dictionary or wordlist has this password, the result will be as below. If our dictionary doesn’t have the password, we have to use another dictionary or wordlist.

    Remember that the choice of dictionary or wordlist will play a key role in WPA/WPA2 password cracking. So that is one way in which we crack wpa wpa2 password  with aircrack for you. Hope this was helpful. Learn how to crack WPA WPA2 with Fern Wifi cracker.