XSS Testing and Prevention Tools

Cross-Site Scripting (XSS) is a security vulnerability that allows an attacker to inject malicious scripts into content from otherwise trusted websites. This can lead to various attacks, including data theft, session hijacking, and defacement.

• Stored XSS: Malicious script is stored on the server and served to users.
• Reflected XSS: Script is reflected off a web server and executed immediately.
• DOM-based XSS: The vulnerability is in the client-side scripts, modifying the DOM of the page.

Various tools can be used for XSS testing, including:

1. Burp Suite: A comprehensive platform for performing security testing.
2. OWASP ZAP: An open-source web application security scanner.
3. XSSer: A tool specifically designed to detect and exploit XSS vulnerabilities.

To defend against XSS, consider the following tools:

1. Content Security Policy (CSP): A security standard that helps prevent XSS attacks by controlling resources the user agent is allowed to load.
2. HTML Purifier: A library that removes malicious code from HTML.
3. OWASP AntiSamy: A tool to sanitize user input.

To enhance security against XSS:

• Always validate and sanitize user inputs.
• Use HTTPOnly and Secure flags for cookies.
• Implement CSP to restrict resources.
• Encode outputs to prevent execution of scripts.