What is Cross-Site Scripting (XSS) and how can it be prevented?

Cross-Site Scripting (XSS) is a type of security vulnerability commonly found in web applications. It occurs when an attacker injects malicious scripts into web pages viewed by other users. This can lead to theft of sensitive information, defacement of websites, and other security risks.

Prevention of Cross-Site Scripting (XSS)

There are several methods to prevent Cross-Site Scripting attacks:

• Input Validation: Sanitize and validate all user input to ensure that only safe data is accepted.
• Encode Output: Encode user input before displaying it on web pages to prevent execution of malicious scripts.
• Use Content Security Policy (CSP): Implement CSP headers to restrict the sources from which content can be loaded on your web application.
• Limit Cookies: Set the HttpOnly flag for cookies to prevent access by scripts, reducing the risk of XSS attacks.
• Regular Security Audits: Conduct regular security audits and penetration testing to identify and fix vulnerabilities before they are exploited.

By implementing these practices, web developers can significantly reduce the risk of Cross-Site Scripting attacks and protect the integrity of their web applications.