Cascade-Hack The Box

Cascade is a Windows machine that just got retired. This had got an active directory which we will try to penetrate in and get the admin privilege.

Let’s begin with the nmap scan

sudo nmap -sS -sV 10.10.10.182

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After doing the map enumeration, I decided to try LDAP enumeration using ldapsearch

ldapsearch -x -b “dc=CASCADE, dc=local” -h 10.10.10.182

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From this enumeration, I found few usernames and something interesting with r.thompson user

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We got a password

Let’s try to decode it.

Here I used the online tool to decode itBase64 Decode and Encode – OnlineDecode from Base64 or Encode to Base64 with advanced formatting options. Enter our site for an easy-to-use online tool.www.base64decode.org

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Now we have the password!

username – r.thompson

password – rY4n5eva

Even though the enumeration with smbclient was not effective in the initial stage and since now we have the username and password lets try login with smbclient.

smbclient -L 10.10.10.182 -U r.thompson

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We got some disks listed, lets try to access each disk using smbclient

smbclient //10.10.10.182/”diskname” -U r.thompson

We have an access to “Data” disk here

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We got some directory listed. Let’s take a stroll through the directories

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Let’s download using smbget

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From the meeting_note.html I found some message which can be useful

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In a directory named Temp, we can see two more directories and in s.smith directory we got a reg file.

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Let’s download this ‘VNC Intsall.reg’ to the local machine (It was already downloaded, but for my ease of use I downloaded it again)

get “VNC Install.reg”

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Virtual Network Computing (VNC) is a graphical desktop-sharing system that uses the Remote Frame Buffer protocol (RFB) to remotely control another computer.

I got this on my local machine and I tried to read it using nano and I got a set of mixed characters. I tried again with cat and I got an interesting password

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“Password”=hex:6b,cf,2a,4b,6e,5a,ca,0f

6bcf2a4b6e5aca0f

We can clone VNC password descriptor form GitHub for cracking this passwordjeroennijhof/vncpwdGitHub is home to over 50 million developers working together to host and review code, manage projects, and build…github.com

I used Metasploit to crack thisfrizb/PasswordDecryptsHandy Stored Password Decryption Techniques VNC uses a hardcoded DES key to store credentials. The same key is used…github.com

Please read the above documentation to see how we are going to decrypt the password

So let’s get Metasploit started and feed the password hash we have

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From the GitHub documentation, I only just replaced the encrypted part

Rex::Proto::RFB::Cipher.decrypt [“6bcf2a4b6e5aca0f”].pack(‘H*’), fixedkey

The decrypted password is “sT333ve2″

Now we have

username: s.smith

password: sT333ve2

We can try to login using Evil-winrmHackplayers/evil-winrmThe ultimate WinRM shell for hacking/pentesting This shell is the ultimate WinRM shell for hacking/pentesting. WinRM…github.com

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https://cdn.embedly.com/widgets/media.html?src=https%3A%2F%2Fgiphy.com%2Fembed%2F3o72Fik5nySn8b0BFe%2Ftwitter%2Fiframe&display_name=Giphy&url=https%3A%2F%2Fmedia.giphy.com%2Fmedia%2F3o72Fik5nySn8b0BFe%2Fgiphy.gif&image=https%3A%2F%2Fi.giphy.com%2Fmedia%2F3o72Fik5nySn8b0BFe%2Fgiphy.gif&key=a19fcc184b9711e1b4764040d3dc5c07&type=text%2Fhtml&schema=giphy

We got the user flag!!

Now we have to find a way to get the root

logging in using smbclient with same username and password and listed Audit$

smbclient //10.10.10.182/Audit$ -U s.smith

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let’s get Audit.db from DB directory

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We can open Audit.db using SQLite

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In Ldap table I found this interesting hash for ArkSvc

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I passed the hash on to google to decode it and I found some compiler had already done some job for me

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We have a new set of username and password

Username: arksvc

Password: w3lc0meFr31nd

let’s try to access using evil-winrm

evil-winrm -u arksvc -p w3lc0meFr31nd -i 10.10.10.182

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Now we have a new shell. But I was confused with next step.

Here I got two users

s.smith and Arksvc, I can’t any difference in

When I went through the files downloaded in the initial period (the one which downloaded using smbget) Isaw a file named ArkAdRecycleBin.log and found this log

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We can see that ArkSvc has permission to move objects to recycle bin.

We got our clue now, lets try to recover the deleted userIntro to Active Directory Backup & Recovery | AD Recovery | Restore AD AccountWhen I was a little kid, I knew what I wanted to be when I grew up. No, not an astronaut. Definitely not a doctor or a…blog.stealthbits.comActive Directory Deleted Objects | Recover & Restore Deleted AD ObjectEditor’s Note: This is the 2 nd in a series of blogs around Active Directory (AD) backup and recovery using…blog.stealthbits.comActive Directory Recycle Bin | Recover Deleted AD Object | AD Deleted ObjectsEditors note: This is the 3rd in a series of blog around Active Directory (AD) backup and recovery using STEALTHbits…blog.stealthbits.com

From the article, I tried the below command

Get-ADObject -filter ‘isDeleted -eq $true’ -includeDeletedObjects -Properties *

and I got TempAdmin’s password

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Form the mail we leaked before, it was clear that TempAdmin password and the current admin password is same

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Let’s decode the password

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Now lets try to be an administrator by

evil-winrm -u administrator -p baCT3r1aN00dles -i 10.10.10.182

y

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We got the root

Just let me know if you have any doubts

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