BANK
- Layout for this exercise:
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1 - INTRODUCTION
- The goal for this exercise is to develop a hacking process for the vulnerable machine Bank, what is a retired machine from the Hack The Box pentesting platform:
https://www.hackthebox.eu/
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2 - ENUMERATION
- Bank's IP is 10.10.10.29:
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- Scanning with Nmap:
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- Connecting to the web browser the result is the Apache default page:
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- Traying to bind Bank's IP with domain bank.htb (usual format for Hack The Box machines) and adding a new line to file /etc/hosts:
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- Now the browser connection is quite different and indeed more promising:
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- Applying DirBuster:
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- Aside from other folders and files we find the folder balance-transfer, what holds a record of a lot of customers' balance transfers:
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- The extension .acc refers to financial account information for Graphic Accounts, a program for creating an maintaining personal budgets, what may include data for bank accounts.
- Reading the first file we find encrypted credentials about a user:
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- Something strikes the attention: while most of the .acc files have a size of around 580 Megabytes, however there is one file with around half the size:
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- Reading that file we find cleartext credentials for the user Chris Christopoulos:
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3 - EXPLOITATION
- First thing we try is SSH with credentials chris:!##HTBB4nkP4ssw0rd!##, though we are not successful:
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- However, we can login to the web application using credentials chris@bank.htb:!##HTBB4nkP4ssw0rd!##
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- Going to the Support tab there is the upload application Choose File:
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- Creating the exploit myshell.htb with Msfvenom:
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- Clicking Choose File and uploading myshell.htb:
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- Also, filling Title and Message fields with any text:
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- Submitting, a ticket is successfully created:
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- Setting a Meterpreter handler listening session:
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- Now, clicking the ticket:
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- The exploitation is successful:
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- Getting a shell and improving it:
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- Also, it may be useful a bash shell:
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4 - CAPTURING THE 1st FLAG
- The user flag is at user.txt:
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5 - PRIVILEGE ESCALATION
- Looking for SUID files:
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- Let's use two ways to achieve a root shell, focusing on files /var/htb/bin/emergency and /etc/passwd
5.1 - /var/htb/bin/emergency
- The file emergency has got the SUID bit so it can be run as root:
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- Let's see what happens when running ./emergency:
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- Surprisingly it leads to a root shell.
5.2 - Modifying /etc/passwd
- We can modify /ect/passwd because it is writable:
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- Creating a new password and encrypting it:
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- Rewriting /etc/passwd so that the password is assigned to the root user:
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- Now, using the new password as root user we achieve a root shell:
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6 - CAPTURING THE 2nd FLAG
- The second flag is at file root.txt:
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