Cross-site Scripting (XSS) is an attack where an attacker’s code is injected into a user’s browser, exploiting the browser’s security context. This code, typically written in HTML/JavaScript but also in VBScript, ActiveX, Java, or Flash, can read, modify, and transmit sensitive data. XSS can hijack user accounts, redirect browsers, or display fraudulent content, thereby compromising the trust between the user and the website. Applications that load content from the file system may execute code in the local machine zone, posing a risk to system security.
To protect against Cross-site Scripting (XSS) attacks, it is crucial to sanitize and validate all user inputs, implement security headers like Content Security Policy (CSP), and ensure that user-generated content is properly escaped before rendering. Utilize secure frameworks that automatically manage XSS protection, regularly update all software to patch vulnerabilities, and conduct ongoing security testing and code reviews to identify and mitigate potential XSS risks.