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Vulnerability DetectionA03:2021

Cross-Site Scripting (XSS) Scanner

Find XSS vulnerabilities that could let attackers inject malicious scripts into your pages.

Cross-site scripting (XSS) allows attackers to inject malicious JavaScript into web pages viewed by other users. Our scanner tests for reflected, stored, and DOM-based XSS across all discovered endpoints, checking input fields, URL parameters, and dynamic content rendering.

What This Scanner Does

Injects XSS payloads into input fields, URL parameters, headers, and cookies. Tests for reflected XSS, DOM-based XSS, and identifies potential stored XSS vectors. Checks whether Content Security Policy headers properly mitigate injection risks.

Why It Matters

XSS can steal session cookies, redirect users to phishing pages, deface your site, or distribute malware. It is the most common web vulnerability and affects virtually every web application that renders user input without proper sanitization.

Common Findings

  • Reflected XSS in search or query parameters
  • DOM-based XSS through client-side JavaScript
  • Missing Content-Security-Policy header
  • Unescaped user input in HTML attributes

OWASP Top 10 Coverage

A03:2021Injection

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