SQL Injection Prevention

Introduction

SQL Injection is a type of security vulnerability that allows an attacker to interfere with the queries that an application makes to its database. This lesson outlines the significance of SQL injection, how it works, and how to prevent it.

What is SQL Injection?

SQL Injection occurs when an attacker is able to submit malicious SQL statements through input fields in a web application, which can lead to unauthorized access to the database, data manipulation, or even data deletion.

How SQL Injection Works

SQL injection exploits the way a SQL query is constructed. For example, consider the following SQL query used in an application:

SELECT * FROM users WHERE username = 'user' AND password = 'pass';

An attacker could manipulate the input to execute arbitrary SQL commands such as:

' OR '1'='1'; --

This input can lead to unauthorized access by bypassing authentication checks.

Prevention Techniques

To prevent SQL Injection, it is essential to follow specific techniques:

• Use Prepared Statements and Parameterized Queries
• Implement Stored Procedures
• Use ORM (Object-Relational Mapping) tools
• Validate and Sanitize User Inputs
• Implement Proper Error Handling

Best Practices

Here are some best practices for securing your application against SQL Injection:

1. Always use prepared statements.
2. Don't expose database error messages to users.
3. Limit database permissions for the application user.
4. Regularly update and patch your database systems.
5. Conduct regular security audits and testing.

FAQ