# Unsanitized User Input in File Path Traversal

## Overview

* **Rule ID**: `java_lang_path_traversal`
* **Applicable Languages**: Java
* **Weakness ID**: CWE-73

## Description

Using unsanitized user input in file paths can jeopardize your system's security. This vulnerability occurs when user input is directly employed to form file names or paths without adequate sanitization, potentially resulting in path manipulation. Attackers may exploit this to access files or directories beyond the intended scope, posing a substantial security risk.

## Remediation Guidelines

* **Avoid** directly constructing file paths using user input, as this practice can inadvertently enable attackers to manipulate paths to access unauthorized files.
* **Instead, utilize path normalization utilities to securely manage user input in file paths**. These utilities help mitigate risks associated with dangerous path sequences.

  ```java
   public class Cls extends HttpServlet
   {
   public void handleRequest(HttpServletRequest request, HttpServletResponse response)
     {
       String image = request.getParameter("user_profile_picture");

       // normalize path
       Path imagePath = Paths.get("user/profile/" + FilenameUtils.getName(image)).normalize();
       File file = new File(imagePath.toString());
     }
   }

  ```

## 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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