Enumeration
Machine IP → 192.168.225.121
Network Scan
Nmap scan → nmap -A -Pn -p- -T4 -o nmap.txt 192.168.225.121
OS Detection → OS: Linux; CPE: cpe:/o:linux:linux_kernel
| Port | Service | Other details (if any) |
|---|---|---|
| 80 | HTTP | nginx 1.10.3 (Ubuntu) |
| 6311 | - | - |
Web Scan
GoBuster scan → gobuster dir -u http://192.168.225.121 -f -w /home/tanq/installations/SecLists/Discovery/Web-Content/directory-list-lowercase-2.3-medium.txt -x html,php,txt
Directories/files listed → wordpress/
Busting the /wordpress/ directory gives the following result →
- index.php (301)
- wp-content/
- wp-login.php
- license.txt
- wp-includes/ (403)
- readme.html
- wp-trackback.php
- wp-admin/ (302)
WPScan determines generic stuff and a user loly. Using this for a brute force attack with command docker run -v /home/tanq/installations/SecLists/:/seclists/ -it --rm wpscanteam/wpscan --url http://192.168.225.121/wordpress/ -U loly -P /seclists/rockyou.txt gives the credentials as loly:fernando for XMLRPC.
Exploitation
Logging in to the /wordpress/wp-login.php as loly may work but does not move forward because of the requests being directed at http://loly.lc instead of the IP address. Therefore, this entry is added to /etc/hosts to enable navigation. Then the login page is visited and login is attempted as loly. This grants the admin page on the wordpress website.
The homepage has a plugin called Adrotate running. On this webpage, a section called “Manage Media”. This says →
1
2
3
4
5
Accepted files: jpg, jpeg, gif, png, svg, html, js and zip. Maximum size is 512Kb per file.
Important: Make sure your file has no spaces or special characters in the name. Replace spaces
with a - or _. Zip files are automatically extracted in the location where they are uploaded
and the original zip file will be deleted once extracted. You can create top-level folders below.
Folder names can between 1 and 100 characters long. Any special characters are stripped out.
Therefore, uploading a reverse shell php code after zipping and uploading could allow navigating to it. The content is stored in the /wordpress/wp-content/banners/ directory. Therefore, a shell is gained by listening on netcat and navigating to the php file in the said path. This is as the user www-data and this gives the user flag.
Privilege Escalation
User
Looking at the wordpress files, the wp-config.php file contains a password lolyisabeautifulgirl. Trying this password for loly, it works and grants the shell as loly.
Root
Looking at the kernel version for the machine (4.4.0-31), there are a list of exploits. Starting with exploits from the highest 4.X version, one worked (45010.c). This gave the root shell and thus the root flag.