Here are some protective measures you could take to protect against XSS.

1. Input Validation and Sanitization

Implement thorough input validation to ensure that user inputs are restricted to expected values. Sanitize input by encoding or escaping special characters.

2. Content Security Policy (CSP)

Utilize Content Security Policy headers to define which sources of content are allowed to be loaded on a web page, reducing the risk of executing malicious scripts.

3. Output Encoding

Encode user-generated content before rendering it on a web page. This prevents browsers from interpreting it as executable code.

4. Use HTTP-Only Cookies

Set the HTTP-only flag on cookies to prevent client-side scripts, including potential XSS scripts, from accessing them.

Conclusion

Understanding XSS vulnerabilities is crucial for web developers and security professionals. By implementing robust input validation, employing security headers, and following best practices, web applications can mitigate the risks associated with Cross-Site Scripting.