What is the code injection attack?

The code injection attack is an attack in which the attacker exploits security vulnerabilities in the web application and introduces or injects code to change the course of execution. A web application becomes vulnerable to code injection attacks mainly when user data is sent to the interpreter without proper validation.

How does the code injection attack work?

The code injection attack works in different ways. Let’s try to understand each type of code injection attack.

Different types of code injection attacks

There are mainly a few common types of code injection attacks:

• SQL Injection Attacks
• HTML Script Injection Attacks
• Dynamic Code Evaluation Attacks
• File Inclusion Attacks
• Shell Injection or Command Injection Attacks

Code injection attacks are mainly found in SQL, LDAP, XPATH, NoSQL, OS commands, XML Parsers, SMTP Headers, etc. Let’s look into some examples to understand these attacks better.

What is the SQL injection attack?

In this type of code injection attack, attackers exploit the security vulnerabilities in the application software and trick the server into executing malicious SQL queries. Thus, the attacker deletes or changes data in the database or steals sensitive data to perform even more attacks.

Example: Suppose username and corresponding sensitive data are stored in a database. A registered user provides a username and corresponding data as requested on a webpage. The server takes the username and executes the following SQL query in the database :

Here, userName is the username, and it is taken as input from the user through a form. At this point, an attacker can input,

And, if proper care is not taken while writing the code, the server will execute the following query: …