引言
SQL注入是一种常见的网络安全漏洞，它允许攻击者通过在输入字段中注入恶意SQL代码，从而控制数据库服务器。GET SHELL是SQL注入的高级阶段，攻击者通过该技术可以获取服务器的最高权限，进而控制整个服务器。本文将详细介绍GET SHELL的五大绝技，帮助读者深入了解这一高级攻击手段。
绝技一：利用错误信息获取权限
- 原理：当数据库在执行SQL语句时遇到错误，会返回错误信息。攻击者可以通过分析这些错误信息，找到数据库的版本、表名、字段名等信息，从而推断出数据库的结构。
- 方法：
- 构造错误的SQL语句，如 `SELECT * FROM table WHERE id = ‘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, 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