XSS allows attackers to inject malicious scripts that execute in users' browsers, stealing sessions, credentials, or performing actions as the user.
Scan for This VulnerabilityCross-Site Scripting occurs when an application includes untrusted data in web pages without proper validation or encoding. The attacker's script runs in the victim's browser with full access to cookies, session data, and the ability to modify page content or make requests as the user.
Session hijacking through cookie theft
Credential theft via fake login forms
Malware distribution
Website defacement
Keylogging and data exfiltration
React, Vue, and Angular encode output by default.
// React - safe by default
return <div>{userInput}</div>;
// BAD - bypasses encoding
return <div dangerouslySetInnerHTML={{__html: userInput}} />;CSP prevents inline scripts from executing.
Content-Security-Policy: default-src 'self'; script-src 'self'Use a library like DOMPurify for user-generated HTML.
import DOMPurify from 'dompurify';
const clean = DOMPurify.sanitize(userHTML);VAS automatically scans for cross-site scripting (xss) and provides detailed remediation guidance.
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