As a programmer, you may be preparing for an interview for your much-coveted job. However, it takes adequate preparation by looking into what questions to expect from the interviewer. One of the common questions usually asked is an exploration of injection attacks in SQL, which often also requires giving an SQL injection example. The query has been explained here to help tip the odds in your favor during the interview.
What is an SQL Injection Attack?
SQL programming language plays a crucial role in web development and management. It is to date the dominantly used method of filtering, retrieving and inserting information from or into a web database. Just like the other databases, an SQL database can be hacked when a hacker exploits weak links in your web application. This type of hack is referred to as SQL injection.
SQL injection attack sounds scary to most people because a hacker can take over your web application, extract user info, discover and reset credentials in a split second. In some cases, the SQL injection attack can be a basis for a major attack on an organization’s network. These attacks aim primarily for the weak points in which the code of your website queries the databases.
SQL Injection Example
SQL Injection attack usually commences with the hacker inserting their malicious code in a particular site’s form field. Examples of such form fields include an email address or password entry fields. Below is an SQL injection example:
Usually, a form field may have the following code:
From members table
WHERE Emailinput = ‘$email_input’;
In this SQL code, the ‘$email_input’ refers to the variable field where the user will enter their email address when logging into the site.
1. The hacker will find a loophole by typing his email with an end quote.
Typically, most email addresses don’t contain quotes, and therefore the system will sanitize the input by omitting the quote.
If it doesn’t, which is what the hacker is hoping for then it would return an ‘internal error’ for instance. The hacker will have gained valuable info on how your site handles errors.
2. The hacker will then run the actual SQL injection attack based on the above information.
An example of such malicious code is:
UPDATE members table
SET email = ‘email@example.com’
WHERE email = ‘firstname.lastname@example.org’;
The hacker cleverly closes the statement after Y in this SQL injection attack example, giving him room to enter a code of his own. This code will change the user email from ‘email@example.com’ to the hackers email ‘firstname.lastname@example.org’. When a password reset link is sent to the account email, the hacker will receive it and gain access to the user’s account.
The above SQL injection example is just one of the simplest examples of how the hacker executes the SQL injection attack. There are more to it than just gaining access to a user account. From there, the hacker can maneuver and bring down the whole web application. When you go through a similar SQL injection example, you will notice that it can be a deadly threat.
You can use this SQL example to identify the weak point of the web application to come up with efficient ways to stop it.