跨站脚本攻击（XSS）的防范措施

在互联网安全领域中，一种常见的安全威胁是跨站脚本攻击（Cross-Site Scripting, XSS），这种攻击利用了Web应用程序对用户输入的不适当处理，允许恶意代码被注入到网站的内容中，从而影响用户的浏览体验甚至造成数据泄露，为了保护Web应用免受XSS攻击的影响,以下是一些有效的防范措施。

对用户输入进行严格的验证和清理

• 输入验证：确保所有从客户端发送过来的输入都经过了严格的身份验证，在接收用户提交的数据时,检查其是否符合预期格式或类型。
• 过滤特殊字符：使用正则表达式或其他手段过滤掉可能包含危险符号或恶意代码的特殊字符,这样可以防止一些常见的XSS漏洞。
• URL编码：对于任何来自外部来源的链接、文件路径等敏感信息,应进行URL编码处理以避免直接执行。

使用HTML实体转换功能

许多现代服务器端语言提供了内置的功能来将HTML实体转换为实际的文本字符，如JavaScript中的htmlspecialchars()函数，通过这种方法,可以有效阻止那些会生成HTML标签的输入。

// 在Node.js环境中使用
const { escape } = require('html-escape');
let userInput = 'I like <script>alert("XSS")</script>';
console.log(escape(userInput)); // 输出: I like 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