CWE-79 (在Web页面生成时对输入的转义处理不恰当(跨站脚本)) — Vulnerability Class 21881

CWE-79 represents a critical input validation weakness where software fails to properly sanitize user-supplied data before rendering it in web pages. Attackers typically exploit this vulnerability by injecting malicious scripts, often JavaScript, into trusted websites. When other users view the compromised page, the embedded code executes in their browsers, allowing the attacker to steal session cookies, hijack accounts, or redirect victims to phishing sites. This breach of trust undermines user privacy and application integrity. To prevent such attacks, developers must implement robust input validation and output encoding strategies. By strictly filtering incoming data and ensuring that all dynamic content is properly escaped before being processed by the browser, developers can neutralize dangerous inputs and effectively mitigate the risk of cross-site scripting vulnerabilities.