SQL Injection: Definition, Types, Examples, and Prevention Methods

SQL Injection is one of the most common cyberattack techniques used to exploit security vulnerabilities in database-driven applications. By manipulating SQL queries, attackers can gain unauthorized access, steal data, or even take full control of a system. Although it is considered a classic attack, many applications remain vulnerable today due to improper handling of user input.

Many people may have heard the term, but still don’t fully understand what SQL Injection is or how it works. In this article, we’ll explain the concept of SQL Injection in detail—covering its definition, simple attack examples, how to perform SQL Injection testing to detect vulnerabilities, and dangerous techniques such as using SQL Injection dorks that are often employed by attackers online.

What Is SQL Injection?

In short, SQL Injection is a method of attack in which an attacker inserts malicious SQL code into a form, URL, or other input field within an application. When the server processes this input, the executed query deviates from what the developer intended, exposing sensitive data.

A simple example: on a login form, if the developer fails to validate user input, an attacker could enter ' OR '1'='1 to bypass authentication and gain access without a valid password.

Types of SQL Injection

There are several common types of SQL Injection attacks:

• Classic SQL Injection → Directly modifies queries to manipulate the database.
• Blind SQL Injection → Conducted without error messages, relying only on the application’s responses (true/false).
• Error-based SQL Injection → Exploits database error messages to reveal information.
• Union-based SQL Injection → Uses the UNION command to retrieve data from other tables.

SQL Injection Cases

SQL Injection is not just theoretical—there have been numerous real incidents involving massive data breaches due to this vulnerability. For instance, attacks on e-commerce websites or online forums have exposed millions of user records.

A classic example is a login bypass. By inserting a specific input into a username or password field, attackers can skip authentication and directly access the admin dashboard.

SQL Injection Testing

To prevent such attacks, developers often perform SQL Injection testing—an assessment to check whether an application is vulnerable.

Testing can be done manually by entering unusual input into forms, or automatically using tools like SQLMap. Regular testing is crucial to identify weaknesses before they can be exploited by malicious actors.

SQL Injection Dorks

In the hacking community, the term SQL Injection dork is quite popular. A “dork” refers to a specialized Google search query designed to locate potentially vulnerable websites. For example, inurl:index.php?id= can be used to find pages with an “id” parameter that might be exploitable.

While attackers often use dorks, understanding how they work is also essential for defenders and developers so they can recognize how hackers find targets and patch vulnerabilities more effectively.

How to Prevent SQL Injection

Fortunately, SQL Injection can be prevented with a few simple but effective practices, such as:

• Always validate user input.
• Use parameterized queries or prepared statements.
• Implement a Web Application Firewall (WAF) to filter malicious traffic.
• Regularly update frameworks, libraries, and database systems.

By following these practices, the risk of SQL Injection attacks can be significantly reduced.

Conclusion

Ultimately, SQL Injection remains one of the most dangerous and persistent security threats today. By understanding how it works, performing regular SQL Injection tests, and avoiding exploitable patterns like SQL Injection dorks, developers and organizations can better protect their valuable data from malicious attacks.

Don’t wait until it’s too late—secure your applications against SQL Injection with the right preventive measures.

Reference

Mesopotamian Journal of CyberSecurity. (2023). SQL Injection Attack: Quick View – Journals. Mesopotamian Journal of CyberSecurity, 2023, 30-34. https://doi.org/10.58496/MJCS/2023/006

Salsabila, H., & Fithra, R. F. (2025). Pemanfaatan SQLMAP untuk Deteksi SQL Injection pada Situs Web. Jurnal Informatika dan Teknik Elektro Terapan, 13(3). https://doi.org/10.23960/jitet.v13i3.6507