What is Code Injection Vulnerability

Aditya Chauhan
2 min readFeb 1, 2023

Code injection is a type of security vulnerability that allows attackers to inject malicious code into a software application, leading to unintended and potentially harmful outcomes. Injection attacks can be performed through user input, such as a web form or query string, and can result in data theft, data manipulation, and unauthorized access to sensitive information.

In this blog, we will discuss code injection and provide a practical example of how it can be performed.

Code Injection: An Overview

Code injection is a method of exploiting software vulnerabilities by injecting malicious code into the application. This code is then executed as part of the normal operation of the software, giving the attacker control over the application and its data.

Code injection attacks can be divided into three main categories:

  1. SQL Injection: This type of code injection attack targets databases and is one of the most common forms of code injection. It occurs when an attacker injects malicious SQL statements into an application’s input fields, allowing the attacker to access, modify, and steal sensitive data.
  2. Command Injection: This type of code injection attack targets operating systems and is used to execute malicious commands on the target system. Command injection attacks are often performed through a web application that allows the attacker to inject commands into the underlying operating system.
  3. Cross-Site Scripting (XSS): This type of code injection attack targets web applications and is used to inject malicious scripts into web pages, which are then executed by the user’s browser. XSS attacks can be used to steal sensitive information, such as login credentials and other personal information.

Practical Example: SQL Injection

SQL injection is one of the most common forms of code injection and is often used to attack databases. Here is a simple example of how SQL injection works.

Suppose an application has a login form that accepts a username and password from the user. The application then checks the user’s credentials against a database to determine if the user is authorized to access the system.

An attacker could take advantage of this by entering a malicious SQL statement into the username field, such as “admin’ OR ‘1’=’1”. The application would then execute this statement, which would bypass the normal authentication process and grant the attacker access to the system.

To prevent SQL injection attacks, it is important to validate user input and sanitize any data that is entered into the application. This can be done by using parameterized queries, which separate user input from the SQL statement, and by validating data to ensure that it meets certain criteria, such as length and type.

In conclusion, code injection is a serious security vulnerability that can lead to devastating consequences. It is important for software developers and security professionals to understand the risks associated with code injection and to take steps to protect their applications and systems from these types of attacks. By following best practices, such as input validation and sanitization, developers can help prevent code injection and protect sensitive data from being stolen or compromised.



Aditya Chauhan

ISO 27001 LA | VAPT | Synack Red Teamer | HTB Dante | HTB RASTA | HTB Cybernetics | HTB Offshore | HTB APTLabs | Cyber Security Analyst | Security Researcher