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# Unsanitized User input in OS command

## Overview

* **Rule ID**: `javascript_lang_os_command_injection`
* **Applicable Languages**: Javascript
* **Weakness ID**: CWE-78

## Description

Executing operating system commands with unsanitized user input can lead to command injection vulnerabilities. This happens when attackers exploit the input to run unauthorized commands, potentially gaining control over the system.

## Remediation Guidelines

* **Do not** directly incorporate user input into OS command execution. This can make the system vulnerable to command injection attacks.
* **Do** use static or predefined values for command parameters whenever possible. This helps reduce the risk of injection and ensures the command operates within expected limits.

  ```java
  let filePattern = "*.js"

  if (req.params.graphql) {
    filePattern = "*.gql"
  }

  cp.exec(`cp ${filePattern} foo`, (error, stdout, stderr) => {});


  ```
* **Do** validate and sanitize all user input used in OS commands. Ensure that the input is free from malicious characters or command sequences.

## References

* [**OWASP command injection explained**](https://owasp.org/www-community/attacks/Command_Injection)
* [**CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')**](https://cwe.mitre.org/data/definitions/78.html)
* [**OWASP Top 10: A03:2021 - Injection**](https://owasp.org/Top10/A03_2021-Injection/)

## Configuration

To omit this rule during a scan, and to provide you with continuous 24/7 code-level scanning, you can employ our [**SAST TOOL**](https://scopy.sec1.io/login)