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# Unsanitized use of FileUpload filename

## Overview

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

## Description

Failure to sanitize filenames from FileUpload can result in path traversal attacks. This vulnerability arises when an attacker manipulates the filename to access files or directories located outside the designated directory.

## Remediation Guidelines

* **Avoid** using unsanitized filenames directly from FileUpload, as attackers can exploit them to navigate the server's directory structure.
* Always sanitize user input when managing file paths. **Utilize** secure methods such as `FilenameUtils.getName()` to ensure the path is protected and cannot be manipulated for directory traversal."

## 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)