Blue

Starting information

• Machine IP : 10.10.10.40
• System : Windows

Network enumeration

I start by modifying my /etc/hosts file to avoid writing the IP everytime :

10.10.10.40 blue

Then I look for open ports with nmap and start an OpenVAS scan:

nmap -p- blue -Pn
Host discovery disabled (-Pn). All addresses will be marked 'up' and scan times will be slower.
Starting Nmap 7.91 ( https://nmap.org ) at 2021-03-02 10:17 CET
Nmap scan report for blue (10.10.10.40)
Host is up (0.039s latency).
Not shown: 65526 closed ports
PORT      STATE SERVICE
135/tcp   open  msrpc
139/tcp   open  netbios-ssn
445/tcp   open  microsoft-ds
49152/tcp open  unknown
49153/tcp open  unknown
49154/tcp open  unknown
49155/tcp open  unknown
49156/tcp open  unknown
49157/tcp open  unknown

Nmap done: 1 IP address (1 host up) scanned in 37.17 seconds

Now I can start nmap scripts on the open port to gather more information:

nmap -p135,139,445,49152,49153,49154,49155,49156,49157 -A -Pn blue

PORT      STATE SERVICE      VERSION
135/tcp   open  msrpc        Microsoft Windows RPC
139/tcp   open  netbios-ssn  Microsoft Windows netbios-ssn
445/tcp   open  microsoft-ds Windows 7 Professional 7601 Service Pack 1 microsoft-ds (workgroup: WORKGROUP)
49152/tcp open  msrpc        Microsoft Windows RPC
49153/tcp open  msrpc        Microsoft Windows RPC
49154/tcp open  msrpc        Microsoft Windows RPC
49155/tcp open  msrpc        Microsoft Windows RPC
49156/tcp open  msrpc        Microsoft Windows RPC
49157/tcp open  msrpc        Microsoft Windows RPC
Service Info: Host: HARIS-PC; OS: Windows; CPE: cpe:/o:microsoft:windows

Host script results:
|_clock-skew: mean: 6m09s, deviation: 1s, median: 6m08s
| smb-os-discovery:
|   OS: Windows 7 Professional 7601 Service Pack 1 (Windows 7 Professional 6.1)
|   OS CPE: cpe:/o:microsoft:windows_7::sp1:professional
|   Computer name: haris-PC
|   NetBIOS computer name: HARIS-PC\x00
|   Workgroup: WORKGROUP\x00
|_  System time: 2021-03-02T09:29:25+00:00
| 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: 2021-03-02T09:29:24
|_  start_date: 2021-03-01T14:16:37

Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 69.34 seconds

Information gathered

Operating System

Windows 7 Professional 7601 Service Pack 1 (Windows 7 Professional 6.1)

Open ports

Vulnerabilities

Here are the vulnerabilities found by OpenVAS:

According to the OpenVAS report, the first vulnerability was disclosed in Microsoft Bulletin MS17-010. A quick search for MS17-010 in metasploit shows that there are exploits available.

EternalBlue exploit

I start metasploit with msfconsole and select the exploit with use exploit/windows/smb/ms17_010_eternalblue. I then configure the following parameters

I launch the attack with exploit and I now have a meterpreter shell with admin privileges:

meterpreter > getuid
Server username: NT AUTHORITY\SYSTEM

This is it! Retrieving the flag from there is a formality. A piece of cake right?