Unsanitized user input in HTTP response (XSS)

Overview

• Rule ID: javascript_express_cross_site_scripting

• Applicable Languages: Javascript

• Weakness ID: CWE-79

Description

Including unsanitized user input in HTTP responses exposes your application to cross-site scripting (XSS) attacks. This vulnerability allows attackers to inject malicious scripts into web pages viewed by other users, posing a significant security risk.

Remediation Guidelines

• Do not include user input directly in a response, as this can lead to XSS vulnerabilities.

  res.send(req.body.data); // unsafe
  

• Instead, sanitize user input before including it in a response. Use library functions or frameworks designed for input sanitization to ensure that user data cannot be interpreted as executable code.

References

• OWASP Cross-Site Scripting (XSS) Cheatsheet

• CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

• OWASP Top 10: 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