Web hacking tactics, particularly those that might harm your apps, are becoming more popular in today’s globe, which is seeing a surge in technological development. SQL Injection is one method of this kind that may be used to attack data-driven applications. You will learn what SQL Injection is and how it utilizes harmful SQL codes to access information that might damage your database in this post. SQL Injection is a kind of SQL injection that is used to acquire information.
What Is SQL Injection?
The SQL Injection vulnerability is a code-based security breach that gives an attacker access to private database information. SQL queries allow attackers to circumvent application security and make changes to, or remove data from, a database. Websites and online applications that rely on relational databases like MySQL, Oracle, or SQL Server are particularly vulnerable to SQL injection attacks. SQL injection attacks have been a common cause of security holes in recent years.
Now that you know the answer to the question “what is SQL Injection,” you can go on to studying the many SQL Injection types.
Types of SQL injection
In-band SQLi is a kind of SQL injection in which the attackers launch their assaults and gather results over the same communication channel.
SQL injections that are based on errors and SQL injections that are based on unions are the two most prevalent forms of in-band SQL injections.
1. Error-based SQL injection: In this version of the attack, the attacker will carry out certain operations that will result in the database producing error messages. You will be able to determine what database it uses, the version of the server where the handlers are hosted, and other relevant information by using the error message.
2. Union-based SQL injection: In this kind of SQL injection, the UNION SQL operator is used to combine the results of two or more select statements issued by the database into a single HTTP response. This type of SQL injection is known as a “union-based” attack. You may construct your queries directly inside the URL, or you can mix numerous statements directly within the input fields in an effort to get a result.
Blind SQLi is a variant of SQL that does not transport data over the web application in this case. When an attack is performed in-band, the attacker is unable to see the results of the assault.
Boolean-based SQL Injection: The attacker will submit a SQL query to the database, requesting it to return a different answer depending on whether the query returns True or False. This kind of SQL injection is known as a Boolean-based SQL injection.
Time-based SQL Injection: The attacker in this attack sends a SQL query to the database, which causes the database to wait for a certain period of time before disclosing the response. This attack is known as a time-based SQL injection. The attacker may determine whether a query is True or False based on how long it takes for the system to respond.
Out-of-bound SQL Injection: Out-of-bound SQL injection is not very common since it is dependent on the capabilities that are enabled on the database server that is being used by the web applications. This makes it difficult to detect and prevent. It’s possible that the database administrator made a mistake with the setup settings.
Now that we’ve covered one of the most significant aspects of SQL injection, it’s time to move on to the second most important aspect of this tutorial, which is how to avoid SQL injection.
How exactly does SQL work when it comes to a website?
The front end, the back end, and the database are the three most important parts of a website.
The frontend of a website is often developed using markup languages such as HTML, CSS, and JavaScript. Scripting languages like Python, PHP, and Perl, among others, are available at the backend of the system. Execution of the queries takes place on the server side using databases such as MySQL, Oracle, and Microsoft SQL Server.
In most cases, submitting a query involves sending a “get request” to the website in question. After that, the website will send you a response with HTML code attached to it.
You are able to test the replies that you obtain from a variety of websites by using the program known as Postman API.
Demo on SQL injection
1. In order to find owasp-damaged online applications, you may use Google Chrome or another browser to:
2. To access this file, please go to sourceforge.net.
3. Access the OWASP Broken Web Applications Project by clicking the Download button.
The Open Web Application Security Project, which annually publishes a list of the top 10 threats to web applications, has created this program. It’s a Virtual Machine with a trove of exploitable web applications.
In order to help students and professionals’ study and perfect their SQL injection techniques, this project intentionally includes vulnerable code.
> To be clear, it is against the law to actually do SQL Injection on any website.
> Launch the OWASP Broken Web Apps VM on a VMware desktop after downloading it.
> The machine’s IP address is shown. Address 192.168.71.132 in this example
> Make use of the IP address shown up above, and go to it using a web browser.
You will discover training apps in addition to practical applications that have been made purposefully susceptible. You may also discover older versions of real-world programs, in addition to a great deal of other content.
You will be using the OWASP Mutillidae II application for the sake of the demonstration.
You can view the OWASP top 10 dangers for 2013, 2010, and 2007, over on the left side of the page.
Simply choose the SQLi – Bypass Authentication > Login option from the menu.
You will then be sent to a standard login authentication screen, the likes of which may be required by any program.
Imagine that you input an anonymous username and password; if you try to log in, you won’t be able to do so.
Let’s attempt to log in once again after we’ve entered a SQL query into the username field.
. My login identifier will be:’or 1=1 —
. To sign in, choose the Login button.
. When you log in to your account this time, you will get a status update stating that it has authenticated the user.
The single quote (‘) operator is used to access the database server, get the default user tables, and then evaluate the specified condition. The criterion you provided, that 1=1, is true in every possible situation. Therefore, it took the first accessible user table in the database and compared it to the criteria, rather than a password.
If you enter a condition that is not true, such as 1=2, you will get the “Account does not exist” warning.
Let’s have a better understanding of the last issue in this tutorial, which is “what is SQL Injection,” now that you have seen a demonstration that showed how a SQL query may be used to log in to an application.
How to Protect Your Database from SQL Injection?
1. Make use of prepared statements and parameterized queries: Parameterized statements guarantee that the SQL parameters that are supplied into the statements will be handled in a secure manner.
2. Object-relational mapping: When it comes to translating SQL result sets into code objects in a smoother manner, the majority of development teams choose to make use of Object Relational Mapping frameworks.
3. Escaping inputs: Escaping inputs is a straightforward method of preventing many forms of SQL injection. This may be accomplished in a number of languages using built-in functions. When constructing a SQL statement in your code base using escape characters, you need to be aware of where the statement is being built.
The following is a list of some of the other approaches that may be utilized to avoid SQL injection:
. Hashing passwords
. Third-party authentication
. Web application firewall
. Purchasing superior software
. Constantly updating and patching software
. Continuously monitoring SQL statements and databases
Conclusion
SQL Injection attacks may take control of a database server hiding behind a web application, allowing the attacker to abuse the database of an organization. As a result of reading this article, you have investigated “what is SQL injection” and the many forms it may take. You were shown a demonstration utilizing the OWASP application, and you gained knowledge on how to avoid SQL Injection.