引言
SQL注入是一种常见的网络安全漏洞，攻击者可以通过在SQL查询中注入恶意代码，从而窃取、修改或破坏数据库中的数据。DVWA（Damn Vulnerable Web Application）是一个专门用于学习和测试网络安全知识的开源项目，其中包含了大量的安全漏洞，包括SQL注入。本文将详细介绍如何在DVWA中实战SQL注入，并提供相应的防御策略。
一、DVWA中的SQL注入漏洞
1.1 登录模块
在DVWA的登录模块中，我们可以通过在用户名或密码字段中注入SQL代码来尝试绕过验证。
实战步骤：
- 打开DVWA登录页面，输入用户名
' OR '1'='1和密码' OR '1'='1，点击登录。 - 如果成功登录，说明存在SQL注入漏洞。
1.2 商品列表模块
在商品列表模块中，我们可以通过在搜索框中注入SQL代码来查询不存在的商品。
实战步骤：
- 打开商品列表页面，输入搜索关键词`1’ UNION SELECT NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 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