Command Injection & 5 Ways to Protect Yourself
Retrieved from NeuraLegion
First of all, what about Command Injection?
For the purpose of executing arbitrary commands on its host operating system, it´s an explotation of a vulnerable application.
Sometimes it´s easy to misunderstand the difference between code injection and command injection, they appear to be the alike. Code injection it´s about attacks letting actors to add malicious code to the applications and then executing it.
Command injection extends the default functionality of an application, tricking it into executing system commands. First of all the threat actors locate a vulnerability in an application so they can run malicious operating system commands, letting the attackers engineer a command, usually an input mechanism like HTML code, cookies or form fields to inject commands into applications, that will cause a desired action in the host operating system to execute.
So, How can I protect my codes from these attacks?
NeuraLegion suggest these next steps.
1. Don’t Run System Commands with User-Supplied Input
Do you need to use user-input for a system command? do not call operating system commands directly. Instead, you can use built-in library functions. It protects the integrity of existing system files that are included, executed, or parsed by your code.
2. Use Strong Input Validation for Input Passed into Commands
You can use a whitelist for strings or allowed characters. To enable users to execute arbitrary commands, for example, you can whitelist certain commands, like ls and pwd, to allow only these input strings.
Alternatively, you can whitelist only allowed characters. However, this method is often less effective, because threat actors constantly come up with inventive techniques to bypass input validation based on whitelists or blacklists.
3. Use the Principle of Least Privilege
This method strives to provide applications and processes with only the minimum privileges they need for their tasks. The goal is to lower the risk and damage of successful attacks. If threat actors manage to inject commands, they are restricted to the privileges allowed to the application or process.
4. Update and Patch Applications Often
Make sure you are up-to-date with patches and updates. This can help keep applications and systems secure and prevent dependencies from introducing command injection vulnerabilities. Additionally, you can use a web application firewall (WAF), which can block suspicious traffic that may include attempted command injection.
5. Test Your Application
One of the simplest and most effective ways to prevent command injections is to scan your application with a dynamic application security testing (DAST) tool.
If you´re interested in finding these kind of tools, don´t hesitate to contact us.
We are always ready to help and find the best tool for you and your company.