> For the complete documentation index, see [llms.txt](https://bunring.gitbook.io/ctf-writeups/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bunring.gitbook.io/ctf-writeups/hack-the-box/2024/blue.md).

# Blue

{% embed url="<https://app.hackthebox.com/machines/Blue>" %}

## Recon

Let's start with an nmap scan.

{% code overflow="wrap" %}

```
┌──(kali㉿kali)-[~]
└─$ nmap -p- -A -T4 192.168.154.129
Starting Nmap 7.94SVN ( https://nmap.org ) at 2024-03-11 03:39 EDT
Nmap scan report for 192.168.154.129
Host is up (0.00012s latency).
Not shown: 65528 closed tcp ports (conn-refused)
PORT      STATE SERVICE      VERSION
135/tcp   open  msrpc        Microsoft Windows RPC
445/tcp   open  microsoft-ds Windows 7 Ultimate 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
Service Info: Host: WIN-845Q99OO4PP; OS: Windows; CPE: cpe:/o:microsoft:windows

Host script results:
| smb-os-discovery: 
|   OS: Windows 7 Ultimate 7601 Service Pack 1 (Windows 7 Ultimate 6.1)
|   OS CPE: cpe:/o:microsoft:windows_7::sp1
|   Computer name: WIN-845Q99OO4PP
|   NetBIOS computer name: WIN-845Q99OO4PP\x00
|   Workgroup: WORKGROUP\x00
|_  System time: 2024-03-11T03:42:02-04:00
| smb2-time: 
|   date: 2024-03-11T07:42:02
|_  start_date: 2024-03-11T17:58:29
| smb2-security-mode: 
|   2:1:0: 
|_    Message signing enabled but not required
| smb-security-mode: 
|   account_used: guest
|   authentication_level: user
|   challenge_response: supported
|_  message_signing: disabled (dangerous, but default)
|_clock-skew: mean: 1h19m59s, deviation: 2h18m33s, median: 0s
|_nbstat: NetBIOS name: WIN-845Q99OO4PP, NetBIOS user: <unknown>, NetBIOS MAC: 00:0c:29:ea:70:5f (VMware)

Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 147.80 seconds
```

{% endcode %}

The SMB output says this is Windows 7 Professional.

There are a couple shares with null session read access (the trick of giving `smbmap` wrong creds works here):

{% code overflow="wrap" %}

```
┌──(kali㉿kali)-[~]
└─$ smbmap -H 192.168.154.129 -u "Kali" -p "kali"
    ________  ___      ___  _______   ___      ___       __         _______
   /"       )|"  \    /"  ||   _  "\ |"  \    /"  |     /""\       |   __ "\
  (:   \___/  \   \  //   |(. |_)  :) \   \  //   |    /    \      (. |__) :)
   \___  \    /\  \/.    ||:     \/   /\   \/.    |   /' /\  \     |:  ____/
    __/  \   |: \.        |(|  _  \  |: \.        |  //  __'  \    (|  /
   /" \   :) |.  \    /:  ||: |_)  :)|.  \    /:  | /   /  \   \  /|__/ \
  (_______/  |___|\__/|___|(_______/ |___|\__/|___|(___/    \___)(_______)
 -----------------------------------------------------------------------------
     SMBMap - Samba Share Enumerator | Shawn Evans - ShawnDEvans@gmail.com
                     https://github.com/ShawnDEvans/smbmap

[*] Detected 1 hosts serving SMB
[*] Established 1 SMB session(s)
                                                                                                
[+] IP: 192.168.154.129:445      Name: 192.168.154.129        Status: Authenticated
        Disk   Permissions     Comment
        ----   -----------     -------
        ADMIN$ NO ACCESS       Remote Admin
        C$     NO ACCESS       Default share
        IPC$   NO ACCESS       Remote IPC
```

{% endcode %}

`Users` has just empty `Default` and `Public` folders.

`nmap` has `vuln` scripts that will check for known vulnerabilities in service. It finds a big one, MS-17-010.

Searching on Exploit DB lead to the following script.

{% embed url="<https://www.exploit-db.com/exploits/41891>" %}

We can use Metasploit to execute this.

<figure><img src="/files/gsZuyl6X5NclM41Rhpla" alt=""><figcaption></figcaption></figure>

`3` is a scanner, we can run that to confirm the vulnerability. `4` needs a backdoor that is already on the system so we can't use it. Let's start with the scan first and then use `0`.

We can run it after entering RHOST.&#x20;

<figure><img src="/files/9uKgzVleEldmYpsld1Z1" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/uUoxSwH6cdq680E1bqou" alt=""><figcaption></figcaption></figure>

We can see the it is indeed vulnerable. We can exploit it.&#x20;

## Initial Access

Coming back to `0` i.e `exploit/windows/smb/ms17_010_eternalblue`. We shall use it now after setting up the options and payload.

<figure><img src="/files/bUwOTwHksqmAZT7vlPDU" alt=""><figcaption></figcaption></figure>

We now have meterpreter shell.

<figure><img src="/files/vk6WCResO6kxFJgbNI9k" alt=""><figcaption></figcaption></figure>

As you can see we are already NT AUTHORITY\SYSTEM which is root access.

<figure><img src="/files/ZkQKKyJDovtSmCnj6UrC" alt=""><figcaption></figcaption></figure>

Now we can just get the flags need.&#x20;

```
C:\Windows\system32>cd \users   

C:\Users>dir
 Volume in drive C has no label.
 Volume Serial Number is A0EF-1911

 Directory of C:\Users

21/07/2017  07:56    <DIR>          .
21/07/2017  07:56    <DIR>          ..
21/07/2017  07:56    <DIR>          Administrator
14/07/2017  14:45    <DIR>          haris
12/04/2011  08:51    <DIR>          Public
               0 File(s)              0 bytes
               5 Dir(s)  17,256,050,688 bytes free

C:\Users>type administrator\desktop\root.txt
[REDACTED]
C:\Users>type haris\desktop\user.txt
[REDACTED]
```