How to do a SQL Injection Attack

Have you ever thought of the thing which is important when you are running a web application? Well, the answer is none other than the database. This thing indicates the fact that one should provide the best security to the database and this is mainly for the sake of the service community. But for an instant just imagine even after you are providing the best network protocol to the database then also any attacker can manipulate the so-called database even without being entering the internal network of the particular company or organization. This is the case we consider with SQL Injection.

This is however considered as the most common attacks used by many known attackers from time to time. So, if you make use of the web application who are connected via working through the database then you must look at what does the SQL injection means and how can it be used so that it will become easy to understand that how does this attack cause problem to our application that does go sometimes beyond our controls.

Also Read: How to Hack a Website and Ethical Hacking Course in Delhi

What is SQL Injection?

SQL injection attacks are a type of security exploit in which an attacker attempts to take advantage of a vulnerability in a website or web application’s code that allows them to inject malicious SQL statements into the application’s database. These statements can then be executed to retrieve sensitive information or modify the contents of the database.

The SQL Injection can be defined as a type of attack in which the attackers can easily access the database connected to a web application just by manipulating the queries with the present input that mainly causes the information to be displayed that was not intended to be visible to all other apart from the owner. Let’s understand the term more precisely. First of all, just consider a web application that uses the database. This is the application that is taking the input from the user and then storing data directly in the database or is fetching data from the database to be displayed. In such a case database query is being generated on the present web application which is being sent to the present database and then is being executed there so that it can be returned the desired output to the very web application.

Apart from this, it is all that takes place. So, when the attackers use the SQL injection then the query that is being generated is to be executed on the database is more likely to be manipulated before only. So, this is the place where it will be performing the present certain actions which the attacks do not have permission to do so. In this, the attackers mainly frame certain SQL statement that is being manipulated the query to be generated by the web application and this is mainly done by injecting some malicious attacks or strings in it. So now this query is being sent to the database. Now as the query is being successfully manipulated then it can be executed to obtain the result in spitting the output that attackers wanted for which the attack was being carried out. The method however is somewhat long and thus also requiring of quite an efficiency.

How to do SQL Injection?

Now let’s see how SQL Injection is being carried out:

SQL injection attacks are carried out by entering malicious SQL statements into an application’s input fields, such as login forms or search bars. These statements are then executed by the application’s database server, giving the attacker access to sensitive information or control over the database.

For example, suppose a website has a login form that accepts a username and password. The website’s code might construct an SQL query to check if the username and password entered by the user match those stored in the database. A hacker could enter a malicious SQL statement into the username field that would cause the database to return all of the usernames and passwords stored within it, effectively bypassing the login process.

Let’s suppose there is a web application. To this very application, one should have the credentials to log in and get inside. The initial requirement is entering the username and password set before. One should remember it as without the log in the further process cannot take place. There are usernames and corresponding passwords of all the potential users stored in the database of the web application you must be used in the first place. While you are attempting to log in to the web application as soon as enter the username and the password it will be generating a corresponding query that is being passed to the database. This will then match the users entered data with all the data which are successfully present in the database of the web application. Only if your data which is entered is matched with any of the data stored then the login will be successful. Even if any of the one data being entered is wrong the entry will be denied for sure. For example, kindly consider if the web application has the following data:

Let’s suppose the attackers entered the login credential of username san_123. This will automatically generate a query such as:

select * from users where username=’San_123′ and password=’1234d678′

Well, this query will surely fetch the whole row of data that is similar to such a credential giving the extract path to the attackers for misuse of the displayed data. When this query is being executed if there is the same username and then giving the corresponding password. Also, if any of the inserted fields does not exactly match then no row will be returned in the response. True value is a success while false is an unsuccessful attempt.

Types of SQL Injection Attacks

There are several types of SQL injection attacks, including:

1. Error-Based SQL Injection

In an error-based SQL injection attack, an attacker attempts to generate an error in the database by entering a malicious SQL statement into an input field. The error message returned by the database can then be used to extract information from the database.

2. Union-Based SQL Injection

In a union-based SQL injection attack, an attacker uses the UNION operator to combine the results of two or more SELECT statements into a single result set. This can be used to extract information from the database.

3. Blind SQL Injection

In a blind SQL injection attack, an attacker attempts to gather information about the database without directly accessing it. This is usually done by sending conditional requests to the database and analyzing the response.

How to Prevent SQL Injection Attacks

There are several ways to prevent SQL injection attacks, including:

1. Parameterized Queries

Using parameterized queries is one of the most effective ways to prevent SQL injection attacks. Parameterized queries use placeholders to separate the SQL code from the user input. This makes it impossible for an attacker to inject malicious SQL code into the query.

2. Input Validation

Input validation is the process of checking user input to ensure that it conforms to expected formats and does not contain any malicious code. This can be done using regular expressions or other methods.

3. Escaping User Input

Escaping user input involves modifying the user input to prevent it from being interpreted as SQL code. This can be done by adding escape characters to the input or using a specialized function to escape the input.

Conclusion:

SQL injection attacks are a serious threat to the security of websites and web applications. However, by using the prevention methods outlined in this article, developers can greatly reduce the risk of their applications being exploited by hackers.

I hope the above information and supporting example was helpful. There are several ways through which SQL injection is been prevented such as by keeping the site up to date, restricting the number of inputs in a web application, reducing the attack surface changes, scanning the site number of times for bugs and of course the use of trusted plugins.   In a cyber security course, you will learn all the methods by which you can prevent any sort of attack on any website.

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