> For the complete documentation index, see [llms.txt](https://docs.sec1.io/user-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sec1.io/user-docs/4-sast/3-javascript/unsanitized-dynamic-input-in-os-command.md).

# Unsanitized Dynamic input in OS Command

## Overview

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

## Description

Incorporating unsanitized dynamic input directly into operating system commands poses a significant security risk. This practice can give attackers the opportunity to execute harmful commands on your system.

## Remediation Guidelines

* **Do use** static, hardcoded values in command strings whenever possible to avoid relying on dynamic data. For example:

  ```java
  let filePattern = "*.js";
  cp.exec(`cp ${filePattern} destinationFolder`, (error, stdout, stderr) => {});

  ```
* When dynamic input is necessary, **sanitize** it to ensure it does not contain malicious code. This can be achieved by validating and escaping the input.

## 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)