What is Cross-Site Scripting (XSS)?
Cross-Site Scripting (XSS) is a type of security vulnerability commonly found in web applications. It allows attackers to inject malicious scripts into web pages viewed by other users. This attack exploits the trust a user has in a particular site, leading to severe consequences such as data theft, credential hijacking, or session hijacking.
Types of XSS
- Stored XSS: Malicious scripts are stored on the server and presented to users each time they access the compromised page.
- Reflected XSS: The payload is reflected off a web server, and executed immediately in the user's browser without being stored.
- DOM-Based XSS: The vulnerability lies in the client-side code rather than the server-side, manipulating the DOM to execute malicious scripts.
Impact of XSS
Successful XSS attacks can lead to unauthorized access to sensitive information, manipulation of webpage content, and phishing attacks, where users are tricked into revealing personal data.
Mitigation Strategies
To prevent XSS, developers should validate and sanitize user input, use content security policies, and encode outputs. Regular security testing, such as penetration testing, can identify XSS vulnerabilities before they are exploited.