What is SQLmap?

SQL Injection is a code injection technique that attackers use to insert malicious SQL statements into input fields for execution by the backend database. This can allow the attacker to view data that they are not authorized to access, manipulate that data, or even execute administration operations on the database, such as shutdown the DBMS. It's a prevalent and dangerous security vulnerability that can exist in any web application that uses an SQL database.

SQLmap Tool

SQLmap is an open-source penetration testing tool that automates the process of detecting and exploiting SQL injection flaws and taking over database servers. It comes with a powerful detection engine, and many niche features. For the ultimate penetration tester, and a broad range of switches lasting from database fingerprinting, data fetching from the database, accessing the underlying file system, and executing commands on the operating system via out-of-band connections.

Using SQLmap for SQL Injection

Using SQLmap for SQL Injection involves several steps. First, you need to identify the URL of the vulnerable website. You can do this by using a tool like Burp Suite to intercept the request and response between your browser and the target website. Once you have identified the vulnerable parameter in the URL, you can use SQLmap to exploit the vulnerability.

Here is a basic example of how to use SQLmap:

  sqlmap -u "http://www.targetsite.com/index.php?id=1" --dbs  

In this example, the "-u" switch is used to specify the URL of the target website. The "--dbs" switch tells SQLmap to enumerate the database names.

Once you have the names of the databases, you can use SQLmap to enumerate the tables within a specific database:

  sqlmap -u "http://www.targetsite.com/index.php?id=1" -D database_name --tables  

In this example, the "-D" switch is used to specify the name of the database, and the "--tables" switch tells SQLmap to enumerate the tables within that database.

From here, you can continue to drill down into the database, enumerating columns within a specific table, and then fetching data from those columns.

It's important to note that SQLmap is a powerful tool, and with great power comes great responsibility. It should only be used for ethical hacking purposes, with permission from the owner of the target website.