Hướng Dẫn Thực Hành : Using Tamper Data with crack_web_form.pl (DVWA): Lesson 5

{ Using Tamper Data with crack_web_form.pl }

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Section 0. Background Information

• What is Damn Vulnerable Web App (DVWA)?
  • Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is damn vulnerable.
  • Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, help web developers better understand the processes of securing web applications and aid teachers/students to teach/learn web application security in a class room environment.
• Pre-Requisite Lab
  • Damn Vulnerable Web App (DVWA): Lesson 1: How to Install DVWA in Fedora 14
• Lab Notes
  • In this lab we will do the following:
    1. We will enable Tamper Data in BackTrack's Firefox
    2. We will use Tamper Data to discover DVWA's HTTP POST DATA string.
    3. We will configure crack_web_form.pl, which was written by computersecuritystudent.com.
    4. We will use crack_web_form.pl to discover the admin password to DVWA.

• Legal Disclaimer
   Tài liệu dùng cho việc nghiên cứu và học tập

Section 1. Configure Fedora14 Virtual Machine Settings

1. Open Your VMware Player
   • Instructions:
     1. On Your Host Computer, Go To
     2. Start --> All Program --> VMWare --> VMWare Player
2. Edit BackTrack Virtual Machine Settings
   • Instructions:
     1. Highlight fedora14
     2. Click Edit virtual machine settings
   • 
3. Edit Network Adapter
• Instructions:
  1. Highlight Network Adapter
  2. Select Bridged
  3. Click on the OK Button.
• 

Section 2. Login to Fedora14

1. Start Fedora14 VM Instance
   • Instructions:
     1. Start Up VMWare Player
     2. Select Fedora14
     3. Play virtual machine
   • 
2. Login to Fedora14
   • Instructions:
     1. Login: student
     2. Password: <whatever you set it to>.
   • 

Section 3. Open Console Terminal and Retrieve IP Address

1. Start a Terminal Console
   • Instructions:
     1. Applications --> Terminal
   • 
2. Switch user to root
   • Instructions:
     1. su - root
     2. <Whatever you set the root password to>
   • 
3. Get IP Address
   • Instructions:
     1. ifconfig -a
   • Notes:
     • As indicated below, my IP address is 192.168.1.106.
     • Please record your IP address.
   • 

Section 4. Temporarily Disable SELINUX and Firewall

1. Start a Terminal Console
   • Instructions:
     1. sestatus
     2. If SELinux status: is set to disabled OR if Current mode: is set to permissive, then skip the next steps, and Continue to the Next Section.
     3. If SELinux status: is set to enabled AND if Current mode: is set to enforcing, then Continue the next steps.
   • Notes:
     • In my case, I need to temporarily put selinux in permissive mode to demonstrate basic attacks on DVWA.
   • 
2. Place selinux in permissive mode
   • Instructions:
     1. echo 0 > /selinux/enforce
        • Placing a "0" in the enforce file, puts selinux in permissive mode.
     2. sestatus
        • Notice that "Current mode:" changed to permissive.
   • 
3. Disable Firewall
   • Instructions:
     1. service iptables save
        • This is not really necessary, unless you have made recent changes to the firewall.
     2. service iptables stop
        • This command disables the firewall.
   • 

Section 5. Configure BackTrack Virtual Machine Settings

1. Open Your VMware Player
   • Instructions:
     1. On Your Host Computer, Go To
     2. Start --> All Program --> VMWare --> VMWare Player
2. Edit BackTrack Virtual Machine Settings
   • Instructions:
     1. Highlight BackTrack5R1
     2. Click Edit virtual machine settings
   • 
3. Edit Network Adapter
   • Instructions:
     1. Highlight Network Adapter
     2. Select Bridged
     3. Do not Click on the OK Button.
   • 

Section 6. Login to BackTrack

1. Start BackTrack VM Instance
   • Instructions:
     1. Start Up VMWare Player
     2. Select BackTrack5R1
     3. Play virtual machine
   • 
2. Login to BackTrack
   • Instructions:
     1. Login: root
     2. Password: toor or <whatever you changed it to>.
   • 
3. Bring up the GNOME
   • Instructions:
     1. Type startx
   • 

Section 7. Open Console Terminal and Retrieve IP Address

1. Open a console terminal
   • Instructions:
     1. Click on the console terminal
   • 
2. Get IP Address
   • Instructions:
     1. ifconfig -a
   • Notes:
     • As indicated below, my IP address is 192.168.1.105.
     • Please record your IP address.
   • 

Section 8. Configure Tamper Data

1. Start Firefox
   • Instructions:
     1. Click on Firefox
   • 
2. Select Add-ons
   • Instructions:
     1. Tools --> Add-ons
   • 
3. Enable Tamper Data
   • Instructions:
     1. Click on Extensions
     2. Click on Tamper Data Enable Button
   • 
4. Restart Firefox
   • Instructions:
     1. Click Restart Now (See Picture)
   • 

Section 9. Capturing HTTP-POST-DATA with Tamper Data

1. Start DVWA
   • Instructions:
     1. Start up Firefox on BackTrack
     2. Place http://192.168.1.106/dvwa/login.php in the address bar.
        • Replace 192.168.1.106 with Fedora's IP address obtained in (Section 3, Step 3).
   • 
2. Engage Tamper Data
   • Instructions:
     1. Tools --> Tamper Data
   • 
3. Start Tamper Data
   • Instructions:
     1. Click on Start Tamper
   • 
4. Login to DVWA
   • Instructions:
     1. Login: admin
     2. Password: password
     3. Click on Login
   • 
5. Tamper with request?
   • Instructions:
     1. Uncheck the Continue Tampering checkbox
     2. Click Submit
   • 
6. Stop Tamper
   • Instructions:
     1. Click on Stop Tamper
   • 
7. Copy POSTDATA String
   • Instructions:
     1. Click on the First POST line.
     2. Right Click on POSTDATA and Select Copy
   • 
8. Start Up Notepad
   • Instructions:
     1. Applications --> Wine --> Programs --> Accessories --> Notepad
   • 
9. Paste Post Data in Notepad
   • Instructions:
     1. Edit --> Paste
   • 
10. Logout of DVWA
    • Instructions:
      1. Click Logout
    • 
11. Record Failed Message
    • Instructions:
      1. Username: admin
      2. Password: wrongpassword
      3. Click Login Button
      4. Right Click on Login failed, Select Copy.
    • 
12. Paste in Notepad
    • Instructions:
      1. Edit --> Paste
    • 
13. Save in Notepad
    • Instructions:
      1. File --> Save
      2. Filename: dvwa-post-data.txt
      3. Click Save
    • 

Section 10. Configuring and running crack_web_form.pl

1. Make Directory
   • Instructions:
     1. mkdir /pentest/passwords/cwf
   • 
2. Download File
   • Instructions:
     1. Start Up Firefox in BackTrack
     2. Input the below URL into the address bar
        • http://www.computersecuritystudent.com/SECURITY_TOOLS/DVWA/DVWAv107/lesson5/cwf.tar.gz
     3. Select Save File Radio Button
     4. Click OK
   • 
3. Save File
   • Instructions:
     1. Click on File System
     2. Click on pentest
     3. Click on passwords
     4. Click on cwf
     5. Click Save
   • 
4. Un-tar Crack Web Form
   • Instructions:
     1. cd /pentest/passwords/cwf
     2. ls -l
     3. tar xovfz cwf.tar.gz
     4. chmod 700 crack_web_form.pl
   • 
5. Crack Web Form Functionality
   • Instructions:
     1. ./crack_web_form.pl -help
   • 
6. Using Crack Web Form
   • Note(FYI):
     • Replace 192.168.1.106 with the IP Address obtained (Section 3, Step 3).
   • Instructions:
     1. ./crack_web_form.pl -U admin -http "http://192.168.1.106/dvwa/login.php" -data "username=USERNAME&password=PASSWORD&Login=Login" -M "Failed Login"
        • -U, Is an optional parameter.  It allows you to specify a username.  If the username is not supplied, then the username will default to admin.
        • -P, Is an optional parameter.  It allows you to specify the location of the password file.  The default password file is set to the password.txt file located in the same directory as crack_web_form.pl.
        • -http, Is a required parameter. It allows to specify the login page.  Supply the login page you used in (Section 9, Step 1).
        • -data, Is a required parameter. It allows you to specify the HTTP POST DATA.
          • username=USERNAME, where USERNAME is either the default "admin" or replaced by the user supplied parameter.
          • password=PASSWORD, where PASSWORD is replaced by values in the password file.
        • -M, Is an optional parameter.  It allows you to specify the authentication failure message.  Supply the failure message you obtained in (Section 9, Step 11).  The default failure message is set to "fail|invalid|error", where the message is case insensitive.
   • 
7. View Crack Web Form results
   • Instructions:
     1. Notice it took 239 attempt to discover the correct password.
   • 

Section 11. Proof of Lab

1. Proof of Lab
   • Instructions:
     1. cd /pentest/passwords/cwf
     2. grep Successful crack_output.txt
     3. date
     4. echo "Your Name"
        • Replace the string "Your Name" with your actual name.
        • e.g., echo "John Gray"
   • Proof of Lab Instructions:
     1. Do a <PrtScn>
     2. Paste into a word document
     3. Email to AnToanThongTin.Edu.VN@Gmail.Com
   •