Understanding Command Injection: Key Insights and Precautions

What is Command Injection?

Command injection is a cyberattack where a hacker executes arbitrary commands through a vulnerable application on a host operating system. This attack allows hackers to exploit different systems within an organization, compromising the entire business data.

Unlike the code injection attack, command injection doesn’t add vulnerable code to the system. Instead, the attacker extends the default functionality that already exists in the application to run malicious commands within a system

Types of Command Injection

Command injection attacks exist in various types, and each of these can lead to major security vulnerabilities. Here are two of the most prominent command injection types.

1. Result-based Command Injection

As the name suggests, result-based command injection is when the attackers directly see the result of a command. This attack produces clear results which are instantly visible.

2. Blind Command Injection

In this, a hacker cannot see the results of an injected malicious code directly but can observe results through time delays in response time and other techniques.

Common Command Injection Attack Vulnerabilities

Here are some fundamental vulnerabilities that might lead to a command injection attack that you must know about.

1. Arbitrary Commands

Some applications allow users to run arbitrary commands on the system, which makes it vulnerable to malicious codes and hence could lead to a command injection attack.

2. Arbitrary File Uploads

Arbitrary file uploads are when users can upload arbitrary file extensions with malicious code to the system.

How to Prevent a Command Injection Attack?

Now that you are aware of some basic vulnerabilities associated with command injection, let’s explore the important prevention techniques for the same.

1. Carefully Validate User Input

The most important prevention practice for command injection attacks is to validate and sanitize user input. Make sure the developers check the input for any special sign or character that could trigger malicious commands or manipulate codes in your app.

2. Leverage the Principle of Least Privilege

As per this principle, a user is only given access to the information required by them to perform their tasks. By limiting access, you can significantly reduce the risk of command injection attacks and keep your web application safe throughout.

3. Regular Security Testing

Make sure you and your team are dedicating ample time to regular security testing of your application. This testing is highly important as it helps identify potential vulnerabilities and eliminate them once and for all.

4. Use Parameterized Commands

You can reduce the risk of command injection attacks by using parameterized commands. These commands ensure that user inputs are passed on the app through a parameter instead of being direct, which lowers the risk of malicious commands entering your app.

5. Stay Updated with the Latest Security Patches

Your developers must be well-versed in the latest security patches and updates so that they can use the same for your applications. By executing the best security updates on your system, you can keep modern cyberattacks like command injections at bay.