cybersec-k

View on GitHub

Basic Pentesting

This is a machine that allows you to practise web app hacking and privilege escalation

Find the services exposed by the machine

This can be done using Nmap. Run sudo nmap -sC -sV -Pn <IP>. If you are unsure how to tackle this, I recommend checking out the Nmap Tutorials by Hack Hunt.

Check the result for Nmap Scan.

What is the name of the hidden directory on the web server(enter name without /)? development

This can be done using GoBuster. Command: gobuster dir -u http://<IP> -w /usr/share/wordlists/dirb/common.txt

GoBuster

Check the file at <IP>/development. Seems like J has a week password.

Let’s use enum4linux to get more information.

This can be done using enum4linux -a <IP>

Check the results for enum4linux

Looks like we got two users jan and *kay

What is the username? jan

What is the password? armando

Now we know the username and we know there is a SSH port. We can use Hydra to get the password. Command: hydra -l <username> -P <wordlist> -t <no._of_threads> ssh://<IP>

Hydra

What service do you use to access the server(answer in abbreviation in all caps)? SSH

To connect ssh jan@<IP>. Enter the password.

Enumerate the machine to find any vectors for privilege escalation.

linPEAS can be used to enumerate through the machine. You can use wget to download a version directly on victim’s machine (if wget is available).

(in another Terminal) Alternatively, if you have a copy on your machine (like I do) scp command can be used. Command: scp <location_of_file jan@<IP>:/tmp

Send LinPEAS

Redirect to /tmp directory. Make linpeas.sh executable; chmod +x linpeas.sh. Run the file; ./linpeas.sh.

What is the name of the other user you found(all lower case)? kay

If you have found another user, what can you do with this information?

RED color is in what we are interested in linPEAS results. If you scroll down, you will come across id_rsa file i.e. PRIVATE KEY of kay

Lineas Result

Open the file.

Kay SSH

Do cat id_rsa. Copy the content and create a id_rsa file on your local machine. Change the permission for the file chmod 600 id_rsa (general form for SSH Keys).

When you try to connect using SSH, it needs a passphrase for the private key.

JohnTheRipper can be used to crack the password. First convert the file using ssh2john.py and then use john with rockyou.txt wordlist.

SSH Pass Crack

Now that we have the passphrase for kay i.e. beeswax. Let’s connect.

SSH via Kay

What is the final password you obtain?

Read the pass.bak file.

Final Pass