SQL Injection is nothing but a cyber attack by which the attackers can hack your SQL database and take all your personal data. It may cause interruption and sometimes they can harass you and demand money for the confidential data.
This type of attack is very common nowadays. Or you can say it is the most common cyber-attack across the globe. In the next; few paragraphs, we are trying to elaborate on what is actually SQL Injection and how it can attack you, and finally, how you can prevent this attack in the future. You can also read; how to protect your computer from hackers.
What is SQL Injection?
SQL injection is a common hacking technique that can trigger major issues within a company. An attacker can easily get around security measures like authentication by using SQL injection.
SQL Injection can be used to trigger serious issues in a variety of ways. An intruder may use SQL Injection to bypass authentication. It gains access to, alters, and deletes data in a database. SQL Injection can be used to execute commands on the operating system in some cases. It allows an attacker to escalate to more damaging attacks within a network protected by a firewall.
How does SQL Injection Work?
In this attack, the hackers put their SQL queries to the web pages like login forms, sign-up forms, contact forms, etc. Any form that is connected to the database. If criminals enter your database, they can steal or manipulate your data, which may change your live website data. Sometimes they modify the database so that they can easily break in in the future.
The hackers sometimes delete the database record, after copying it and then demand a huge ransom for the database. So, your responsibility is to secure the database as much as possible.
In the next paragraph, we will share some tips and ideas on how to prevent these attacks in the future, and if it will happen to you how can you save your database. Before that, let us discuss the types of SQL injections.
Different Types of SQL Injection
Here in this section, we will discuss the type of SQL Injection in cyber attacks. In-band SQLi, inferential SQLi, and out-of-band SQLi are the three main types of SQL injection in a cyber attack.
1. In-band SQLi (Classic SQLi)
The most popular and easy-to-exploit SQL Injection attack is in-band SQL Injection. Here an attacker can execute the attack. It can also collect the results using the same communication channel. Error-based SQL injection and Union-based SQL injection are the two most popular forms of it.
Error-based SQLi: This technique uses the database server’s error messages to collect knowledge about the database’s structure. An attacker may often enumerate an entire database using only error-based SQL injection. Although errors are useful during the creation process of a web application, they should be disabled on a live site or logged to a secure file.
Union-based SQLi: This technique uses the UNION SQL operator to combine the results of two or more SELECT statements into a single output. It is then returned as part of the HTTP response.
2. Inferential SQLi (Blind SQLi)
Unlike in-band SQLi, inferential SQL Injection takes longer for an attacker to manipulate. It is, however, just as dangerous as any other SQL Injection process. No data is transmitted through the web application in an inferential SQLi attack.
The attacker cannot see the outcome of an attack in a band. That is why such attacks are widely referred to as “blind SQL Injection attacks”. Instead, by sending payloads, monitoring the web application’s response, and the database server’s subsequent actions, an attacker can recreate the database structure. Blind-boolean-based SQLi and Blind-time-based SQLi are the two forms of inferential SQL injection.
Boolean-based (content-based) Blind SQLi: It is an inferential SQL Injection technique that uses a SQL query to compel the application to return a different answer depending on whether the query returns TRUE or FALSE.
The content of the HTTP answer will alter or stay the same depending on the outcome. Even if no data from the database is retrieved, an attacker may assume whether the payload used returned true or false. Since an attacker will have to enumerate a database character by character, this attack is usually slow (especially on large databases).
Time-based Blind SQLi: It is an inferential SQL Injection technique that uses a SQL query to force the database. It waits for a set amount of time (in seconds) before responding. The attacker would be able to tell whether the question result is TRUE or FALSE based on the response time.
An HTTP response will be returned with a pause or instantly, depending on the outcome. Even if no data from the database is retrieved, an attacker may assume whether the payload used returned true or false. Since an attacker will have to enumerate a database character by character, this attack is usually slow (especially on large databases).
3. Out-of-band SQLi
It is uncommon and relies on functionality being available on the database server that the web application uses. When an intruder is unable to launch and gather data through the same channel, out-of-band SQL Injection occurs.
Out-of-band techniques give an attacker a better option than inferential time-based techniques, particularly if server responses aren’t always consistent (making an inferential time-based attack unreliable).
This technique will depend on the database server’s ability to send data to an attacker via DNS or HTTP requests. Such is the case with the XP dir tree command in Microsoft SQL Server. It can be used to send DNS requests to a server controlled by an attacker. The UTL HTTP package in the Oracle Database can be used to send HTTP requests from SQL and PL/SQL to a server controlled by an attacker.
How to Prevent SQL Injection
This type of attack takes place when you are not aware. And it is very hard to keep an eye on the database all the time. But before securing our database, we need to generate awareness, spread awareness, find the faults, the issues, the leaks, and the loopholes, and try to repair or solve them. Thus you can close the doors of your database.
Always test your database and check every day at least once. It is better to take a backup every day so, that if by any chance, this attack occurs, you can upload the backup, delete all the malicious codes, and save the database and website immediately.
Try to hire smart developers and build a secure website. And keep updating so that no error can attract hackers. If you develop a secure software or website, it makes you safer and nobody can take control of your system.
Conclusion
As we discussed earlier, we need to secure our development and have to be more careful with our database. We need to buy SSL for our server, which can prevent some attacks by hackers. It is good not to choose cheap hosting and domain, which may bring you several attacks. But the most important is to generate more awareness of the surroundings and educate people with this information.
Through this topic, we have tried to cover the most important information about SQL injection. You also check our guide to protect yourself from phishing. I hope this article was helpful to you. If you liked the article, share it with your friends and family. If you have some suggestions, do not hesitate to leave them in the comments section below. We will add that to the article.