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Relevant

This is a write-up for the room on TryHackMe located at: https://tryhackme.com/room/relevant

Nmap Scan:

I ran nmap -T4 -A 10.10.161.100 -oN nmap_output, however this did not get me anywhere. It seemed to me that the host was blocking ping probes. I then ran nmap -Pn 10.10.161.100:

Host discovery disabled (-Pn). All addresses will be marked 'up' and scan times will be slower.
Starting Nmap 7.91 ( https://nmap.org ) at 2021-06-03 15:25 EDT
Nmap scan report for 10.10.161.100
Host is up (0.23s latency).
Not shown: 997 closed ports
PORT STATE SERVICE
135/tcp filtered msrpc
139/tcp filtered netbios-ssn
3389/tcp filtered ms-wbt-server

Nmap done: 1 IP address (1 host up) scanned in 120.16 seconds

I later ran sudo nmap -p- -Pn -sS -A 10.10.161.100 -oN fullscan.txt which got me way more information**:**

Host discovery disabled (-Pn). All addresses will be marked 'up' and scan times will be slower.
Starting Nmap 7.91 ( https://nmap.org ) at 2021-06-03 15:37 EDT
Nmap scan report for 10.10.161.100
Host is up (0.22s latency).
Not shown: 65527 filtered ports
PORT STATE SERVICE VERSION
80/tcp open http Microsoft IIS httpd 10.0
| http-methods:
|_ Potentially risky methods: TRACE
|_http-server-header: Microsoft-IIS/10.0
|_http-title: IIS Windows Server
135/tcp open msrpc Microsoft Windows RPC
139/tcp open netbios-ssn Microsoft Windows netbios-ssn
445/tcp open microsoft-ds Windows Server 2016 Standard Evaluation 14393 microsoft-ds
3389/tcp open ssl/ms-wbt-server?
| rdp-ntlm-info:
| Target_Name: RELEVANT
| NetBIOS_Domain_Name: RELEVANT
| NetBIOS_Computer_Name: RELEVANT
| DNS_Domain_Name: Relevant
| DNS_Computer_Name: Relevant
| Product_Version: 10.0.14393
|_ System_Time: 2021-06-03T19:48:50+00:00
| ssl-cert: Subject: commonName=Relevant
| Not valid before: 2021-06-02T19:27:43
|_Not valid after: 2021-12-02T19:27:43
|_ssl-date: 2021-06-03T19:49:26+00:00; 0s from scanner time.
49663/tcp open http Microsoft HTTPAPI httpd 2.0 (SSDP/UPnP)
| http-methods:
|_ Potentially risky methods: TRACE
|_http-server-header: Microsoft-IIS/10.0
|_http-title: IIS Windows Server
49667/tcp open msrpc Microsoft Windows RPC
49669/tcp open msrpc Microsoft Windows RPC
Warning: OSScan results may be unreliable because we could not find at least 1 open and 1 closed port
Device type: general purpose
Running (JUST GUESSING): Microsoft Windows 2016|2012|2008 (91%)
OS CPE: cpe:/o:microsoft:windows_server_2016 cpe:/o:microsoft:windows_server_2012 cpe:/o:microsoft:windows_server_2008:r2
Aggressive OS guesses: Microsoft Windows Server 2016 (91%), Microsoft Windows Server 2012 (85%), Microsoft Windows Server 2012 or Windows Server 2012 R2 (85%), Microsoft Windows Server 2012 R2 (85%), Microsoft Windows Server 2008 R2 (85%)
No exact OS matches for host (test conditions non-ideal).
Network Distance: 4 hops
Service Info: OSs: Windows, Windows Server 2008 R2 - 2012; CPE: cpe:/o:microsoft:windows

Host script results:
|_clock-skew: mean: 1h24m00s, deviation: 3h07m51s, median: 0s
| smb-os-discovery:
| OS: Windows Server 2016 Standard Evaluation 14393 (Windows Server 2016 Standard Evaluation 6.3)
| Computer name: Relevant
| NetBIOS computer name: RELEVANT\x00
| Workgroup: WORKGROUP\x00
|_ System time: 2021-06-03T12:48:49-07:00
| smb-security-mode:
| account_used: guest
| authentication_level: user
| challenge_response: supported
|_ message_signing: disabled (dangerous, but default)
| smb2-security-mode:
| 2.02:
|_ Message signing enabled but not required
| smb2-time:
| date: 2021-06-03T19:48:51
|_ start_date: 2021-06-03T19:28:19

TRACEROUTE (using port 139/tcp)
HOP RTT ADDRESS
1 59.97 ms 10.2.0.1
2 ... 3
4 200.41 ms 10.10.161.100

OS and Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 722.09 seconds

Foothold:

I needed to find a way into the system, or a foothold. I browsed to the IP address:

I wanted to see if SMB is being ran on this page, I then used metasploit to find out what version of SMB was running:

I then ran a nmap script just for smb "nmap --script smb-os-discovery 10.10.161.100":

Host script results:
| smb-os-discovery:
| OS: Windows Server 2016 Standard Evaluation 14393 (Windows Server 2016 Standard Evaluation 6.3)
| Computer name: Relevant
| NetBIOS computer name: RELEVANT\x00
| Workgroup: WORKGROUP\x00
|_ System time: 2021-06-03T13:22:34-07:00

I believed that smb is my way in. I then ran smbclient:

I then noticed a unique Sharename nt4wrksv. I wanted to see what's in here. So I ran smbclient to have access to the share:

I then saw a passwords.txt file.

I then wanted to download it:

I was able to then read the password file on my local system:

The passwords were encoded, and it seemed to be base64 to me. Using https://www.base64decode.org/ I was able to decode the text:

To me, this seemed like a login for an smb user. Viewing this writeup, I noticed that the decoded had made me miss another password. I then had 2 logins:

I did not know what tool to use next to get further. I then used the same write-up and noticed that I would have to use psexec which is located in /usr/share/doc/python3-impacket/examples. I was then able to run it on the SMB:

The user for Bill did not work:

Now I wanted to move back and see another way inside. Both port 80 and 49663 both are running the same website:

I then ran dirsearch on the port 49663:

At this point we have access to a website which has the same contents as the smb server:

Exploitation:

In order to exploit this system, I will have to create a payload to then submit to the samba share. I will have to use msfvenom in order to create this. I uploaded a .exe and it did not work. I had to find another format to upload the file to. I then looked at the same aforementioned writeup to see what format they used. They used .aspx. I also did not know that Windows Server 2016 is a x64 architecture. With those in mind, I then made a payload:

I then had to upload this to the smb server:

I then have to go to the web version on the payload so that way it can be initiated. Before I do that, I have to have a netcat listener open on another terminal. The payload worked:

Browsing around the file system I found the user flag:

This was my first Windows machine, so I had to refer to the write-up to know where to go next. I then learned that I would have to upload an exe called PrintSpoofer which impersonates privileges. I then downloaded it:

I then had to upload it. I did this using the same method as I did for the payload:

I then ran:

PrintSpoofer.exe -i -c cmd

which led me to this:

I then went to the Desktop of the Administrator and got the flag:

What I Learned:

I learned a lot from this machine. It was my first Windows machine so there was a little learning curve for me while attempting this machine. I learned about whoami /priv which was not something I had known about previously. Overall, a great Windows machine, however NOT recommended for Windows machine beginners.