What Is SQL Injection?

What Is SQL Injection

If you have come across the term ‘SQL Injection’ and always wondered what it meant, the answer is that SQL stands for ‘Structured Query Language, and so by default SQL Injection must mean ‘Structured Query Language Injection’. If you are still somewhat bemused, then we can assure you, once you have read the rest of this article you will have a fuller explanation which hopefully clarifies it for you.

We will state from the outset that SQL Injection is not desirable, and in truth, it can cause individuals, businesses, and organisations no end of problems. The clue is the word ‘injection’ and the fact that an SQL injection is an attack by hackers or cybercriminals on the database of an online property such as a website, and the queries made to it by applications.

What Can Happen During An SQL Injection?

Some SQL injection attacks can cause nothing more than an inconvenience at one end of the scale, through to a full-scale attack on the website’s server and its data or the disabling of a website so that it cannot function.

One of the consequences can also be that any data held is compromised which can be a huge nightmare for companies that hold highly sensitive private data such as bank and credit card details or the medical data of individuals. Logins and passwords can also become vulnerable during an SQL injection attack, fraudulent data and records can be created, and malicious code can also be introduced.

Many of these attacks use what are called ‘operators’. These operators act as commands that cause the servers of a website is housed to operate or act in ways that help the hackers. You will see some of these in the next section.

SQL Injection Attack Types

Here are some specific examples of SQL Injection attacks.

Error-Based: It might surprise you that error messages often include information useful to hackers. For this reason, they use SQL injections to generate error messages from the database server.

Union-Based: When the operator UNION is used, it causes two queries to return a single set of data. The attackers then use that data to generate further results and thus extract ever-increasing amounts of data.

Blind Injection: If an application is vulnerable to SQL injection attacks, a hacker will query the database looking for TRUE or FALSE responses. This can be done using a content-based or time-based SQL injection.

Content-Based: A query is sent to the database server with a conditional statement. The hackers then look for TRUE or FALSE conditions from the query and that response assists them in further understanding the server.

Time-Based: A query is sent to the database server, and the time taken for the response indicates whether it is TRUE or FALSE and this provides the information that the hacker needs.

Protecting Against SQL Injection Attacks

We are sure that many of you reading this will want to know if, and how, you can prevent an SQL injection attack on your website and data server. The good news is that there are ways to prevent them, and here are some of the most effective.

Test For Vulnerabilities: A primary way of preventing attacks is to check to see if your database server is vulnerable to them using one of the many tools available for such tests and then taking action to resolve that vulnerability.

Regularly Update Software: This applies to any system, be it your home computer or your company’s database. Software developers regularly issue updated security for their systems so make sure you are using the latest version.

Control Access To Your Database: Ensure that you control who can access your database and servers and what they can access. The fewer that do, the fewer pathways a hacker has to access it.

Use Encryption: One of the most used and also one of the most robust means of securing your database from SQL injection attacks is encryption. Even if a hacker got past some of the more basic security, they would not be able to decipher the data protected by encryption keys.