How can you limit user and application privileges with access control?

1 What is SQL injection?

SQL injection is a common attack method that exploits a vulnerability in a web application that interacts with a database. The attacker injects malicious SQL statements into the input fields or parameters of the application, which are then executed by the database. This can result in data leakage, modification, deletion, or even complete takeover of the database.

2 How to prevent SQL injection?

One of the best ways to prevent SQL injection is to use parameterized queries or prepared statements. These are SQL statements that separate the structure and the data, so that the database can distinguish between code and input. Parameterized queries or prepared statements prevent the attacker from changing the logic of the query and executing arbitrary commands. For example, in PHP, you can use PDO or mysqli to create parameterized queries or prepared statements.

5 How to limit privileges?

The principle of least privilege is a key principle of access control, which states that each user or application should have only the minimum privileges necessary to complete their tasks. This way, you can reduce the risk of unauthorized or malicious actions, as well as the impact of SQL injection or other attacks. To limit privileges, you can grant only the required privileges to each role and revoke any unnecessary or unused privileges. Additionally, you can use read-only or write-only privileges for data access, depending on the need. Furthermore, column-level or row-level privileges can be used to restrict access to sensitive or confidential data. Additionally, stored procedures or functions can be used to encapsulate complex or frequent operations and grant privileges only to execute them. Lastly, views can be created to create virtual tables that filter or aggregate data and grant privileges only to access them.