2.2.5. SQL Injection

Definition: An attacker exploits vulnerabilities in an application’s database layer by injecting malicious SQL commands.

SQL Injection is a type of cyber attack where an attacker manipulates an application's database layer. This is done by injecting harmful SQL code into an input field that the application processes. If the application does not properly validate the input, the SQL commands get executed against the database, potentially allowing the attacker to access or manipulate sensitive data.

Imagine you are trying to enter a club, and the bouncer only checks if your name is on a VIP list. If someone walks up and says, 'I'm on that list, and I'm also a police officer,' the bouncer might just let them in without verifying. Similarly, if a website does not check if an input is safe before using it in a database command, it risks letting unauthorized commands in.

Example: Entering ' OR 1=1-- into a login field can bypass authentication in poorly coded applications.

The example provided demonstrates how an SQL Injection attack can bypass security measures like authentication. When an attacker enters the SQL command ' OR 1=1-- into a login field, the statement confuses the SQL interpreter of the application. Instead of checking for valid user credentials, the injected SQL command makes the database return true for any user, allowing the attacker to gain unauthorized access.

Think about a locked door that only opens for certain passwords. If someone learns that saying 'open' is equivalent to a magic phrase that opens the door, they can sneak right in without needing the correct password. In a similar way, SQL Injection exploits vulnerabilities in software that does not properly verify requests.

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