# Unsanitized dynamic input in file path

## Overview

* **Rule ID**: `javascript_lang_non_literal_fs_filename`
* **Applicable Languages**: Javascript
* **Weakness ID**: CWE-73

## Description

Permitting unsanitized dynamic input in file paths can result in unauthorized access to files and folders. This vulnerability occurs when dynamic data is used in file system operations, potentially enabling attackers to gain access to restricted or hidden files and folders.

## Remediation Guidelines

* **Ensure** that all dynamic data and function arguments are sanitized before using them in file system operations. This is essential to prevent unauthorized access.
* **Use a combination of hard-coded string literals** and control logic rather than directly passing dynamic data or function arguments to file system functions. This approach enhances safety.

  ```java
  function write(filename) {
    switch(filename) {
      case "hello.txt":
        fs.writeCreateFile("hello.txt");
        break;
       // Add more cases as necessary
     }
   }
  ```

## References

* [**OWASP path traversal**](https://owasp.org/www-community/attacks/Path_Traversal)
* [**CWE-73: External Control of File Name or Path**](https://cwe.mitre.org/data/definitions/73.html)
* [**OWASP Top 10: A04:2021 - Insecure Design**](https://owasp.org/Top10/A04_2021-Insecure_Design/)

## 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)


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