(Damn
Vulnerable Web App (DVWA):
Lesson 10)
{ Cross Site Request
Forgery combined with curl }
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 Labs
-
Lab
Notes
- In this lab we will do the following:
- We will test a basic Cross Site Request
Forgery (XSRF) attack
- We will capture and manipulate a CSRF
URL to change the admin password.
- We will obtain the session cookie
string using a reflective XSS attack.
- We will create a curl CSRF string to
change the admin password.
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- In addition, this is a teaching website
that does not condone malicious behavior of
any kind.
- Your are on notice, that continuing
and/or using this lab outside your "own" test environment
is considered
malicious and is against the law.
- © 2012 No content replication of any
kind is allowed without express written permission.
Section 1:
Configure Fedora14 Virtual Machine Settings |
- Open Your VMware Player
- Instructions:
- On Your Host Computer, Go To
- Start --> All Program --> VMWare --> VMWare Player
- Edit Fedora14 Virtual Machine Settings
- Instructions:
- Highlight fedora14
- Click Edit virtual machine settings
- Edit Network Adapter
- Instructions:
- Highlight Network Adapter
- Select Bridged
- Click on the OK Button.
Section 2:
Login to Fedora14 |
- Start Fedora14 VM Instance
- Instructions:
- Start Up VMWare Player
- Select Fedora14
- Play virtual machine
- Login to Fedora14
- Instructions:
- Login: student
- Password: <whatever you set
it to>.
-
Section 3:
Open Console Terminal and Retrieve IP Address |
- Start a Terminal Console
- Instructions:
- Applications --> Terminal
- Switch user to root
- Instructions:
- su - root
- <Whatever you set the root password to>
-
- Get IP Address
- Instructions:
- 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 |
- Start a Terminal Console
- Instructions:
- sestatus
- 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.
- 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.
- Place selinux in permissive mode
- Instructions:
- echo 0 > /selinux/enforce
- Placing a "0" in the enforce file,
puts selinux in permissive mode.
- sestatus
- Notice that "Current mode:" changed
to permissive.
-
- Disable Firewall
- Instructions:
- service iptables save
- This is not really necessary,
unless you have made recent changes to the firewall.
- service iptables stop
- This command disables the firewall.
Section 5: Configure BackTrack Virtual Machine Settings |
- Open Your VMware Player
- Instructions:
- On Your Host Computer, Go To
- Start --> All Program --> VMWare -->
VMWare Player
- Edit BackTrack Virtual Machine Settings
- Instructions:
- Highlight BackTrack5R1
- Click Edit virtual machine settings
- Edit Network Adapter
- Instructions:
- Highlight Network Adapter
- Select Bridged
- Do not Click on the OK Button.
Section 6: Login to BackTrack |
- Start BackTrack VM Instance
- Instructions:
- Start Up VMWare Player
- Select BackTrack5R1
- Play virtual machine
- Login to BackTrack
- Instructions:
- Login: root
- Password: toor or <whatever you changed
it to>.
- Bring up the GNOME
- Instructions:
- Type startx
Section 7: Open Console Terminal and Retrieve IP Address |
- Open a console terminal
- Instructions:
- Click on the console terminal
- Get IP Address
- Instructions:
- ifconfig -a
- Notes:
- As indicated below, my IP address is
192.168.1.105.
- Please record your IP address.
- Start Firefox
- Instructions:
- Click on Firefox
- Login to DVWA
- Instructions:
- Start up Firefox on BackTrack
- 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).
- Login: admin
- Password: password
- Click on Login
Section 9: Set Security Level |
- Set DVWA Security Level
- Instructions:
- Click on DVWA Security, in the left
hand menu.
- Select "low"
- Click Submit
Section 10: Cross
Site Request Forgery |
- CSRF Menu
- Instructions:
- Select "CSRF" from the left
navigation menu.
-
- Basic CSRF Test
- Instructions:
- New password: abc123
- Confirm new password: abc123
- Click Change
- View Password Change Results
- Notes:
- Below the change button you will notice
the message that says "Password Changed."
- What I really want you to notice is the
URL string.
- See how the URL string has the below
two parameters separated by a "&".
- password_new=abc123
- password_conf=abc123
- This is DVWA's example of bad
implementation of how to change a password on a web application for
the following reasons:
- http is being used instead of https,
which means this password change was in clear text.
- An attacker could manipulate the URL
string using the address bar or curl to change the password.
- Continue to next step
- Address Bar CSRF Test
- Instructions:
- In the URL, after password_new=,
replace abc123 with test123.
- In the URL, after password_conf=,
replace abc123 with test123.
- Click the Reload Current Page Arrow
- Notes:
- Notice the Password is changed
- Copy CSRF URL
- Instructions:
- Highlight the URL
- Right Click
- Copy
- Start Notepad
- Instructions:
- Applications --> Wine --> Programs -->
Notepad
- Paste URL into Notepad
- Instructions:
- Edit --> Paste
Section 11: Test
Password Change |
- Logout of DVWA
- Instructions:
- In the Left Navigation Menu, Click
Logout
- Login to DVWA
- Instructions:
- Username: admin
- Password: test123
-
- Set DVWA Security Level
- Instructions:
- Click on DVWA Security, in the left
hand menu.
- Select "low"
- Click Submit
Section 12: XSS
reflected |
- XSS reflected
- Instructions:
- Select "XSS reflected" from the left menu
navigation.
- Submit cookie XSS attack
- Instructions:
- What's your Name? <script>alert(document.cookie)</script>
- Click Submit
-
- Copy Cookie String
- Instructions:
- Highlight The Cookie String
- Edit --> Copy
- Click the OK button
- Paste Cookie into Notepad
- Instructions:
- Go back to your notepad
- Edit --> Paste
Section 13: Build
Curl String |
- Open a console terminal
- Instructions:
- Go to notepad
- In notepad type the
following
- curl --cookie "" --location
""
- Place the cookie string
between the quotes after the --cookie tag.
- Place the html string
between the quotes after the --location tag.
- Your string should now look
like the below line and picture
- curl --cookie "security=low;
PHPSESSID=3juclcme0enmmhns9t36mi4ij0" --location
"http://192.168.1.106/dvwa/vulnerabilities/csrf/?password_new=test123&password_conf=test123&Change=Change#"
- Replace the "test123"
password with "password"
- curl --cookie "security=low;
PHPSESSID=3juclcme0enmmhns9t36mi4ij0" --location
"http://192.168.1.106/dvwa/vulnerabilities/csrf/?password_new=password&password_conf=password&Change=Change#"
- Copy Curl String
- Instructions:
- Highlight Curl String
- Edit --> Copy
- Open a console terminal
- Instructions:
- Click on the console terminal
- Execute Curl String
- Instructions:
- cd /root
- Edit --> Paste
- Append the following to your
curl string
- | grep "Password Changed" |
tee curl.txt
- Press <Enter>
-
- Verify Curl Results
- Notes:
- Your should see the Password
Changed message you saw earlier, when you changed your
password using the CSRF menu.
Section 14:
Test Curl String
Password Change |
- Logout of DVWA
- Instructions:
- In the Left Navigation Menu, Click
Logout
- Login to DVWA
- Instructions:
- Username: admin
- Password: password
-
- Welcome to DVWA
- Notes:
- If you see the Welcome Screen,
then you have successful use curl to change the password
remotely without a browser.
-
- Proof of Lab
-
Proof of Lab Instructions:
- Pull up a BackTrack Terminal Window
- cd /root
- ls -l | grep curl.txt
- grep -i "password change" curl.txt
- date
- echo "Your Name"
- Replace the string "Your Name" with
your actual name.
- e.g., echo "John Gray"
- Do a <PrtScn>
- Paste into a word document
- Upload to Moodle
-
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