Host a single binary file without needing administrative privileges

Invoke-HostFile.ps1

Function Invoke-HostFile {
    <#
        .SYNOPSIS
            
            Hosts a base64 string representation of a binary file or a given
            $FilePath on the specified $Port. Any HTTP request to the given 
            host/port will return the binary data of the specified file.

        .PARAMETER Base64File
        
            Base64 string of a binary file.

        .PARAMETER FilePath

            Path of local file to host.

        .PARAMETER Port
    
            Port to host the file on, defaults to 8000.

        .PARAMETER ServerSleep
    
            Time (in seconds) to sleep before killing the webserver.

        .PARAMETER FireWallRule

            Switch. Add/remove a local firewall rule (needs local admin).

        .EXAMPLE

            Invoke-HostFile -Base64File "UEs..." -Port 80

            Host the base64 encoded file on port 80.

        .EXAMPLE

            Invoke-HostFile -FilePath file.exe -Port 8000 -FireWallRule

            Host the specified local file encoded file on port 8000, adding/removing
            a local firewall rule.
    #>
    param ( 
        [String]
        $Base64File,

        [ValidateScript({Test-Path -Path $_ })]
        [String]
        $FilePath,

        [Int]
        $Port = 8000,

        [Int]
        $ServerSleep = 60,

        [Switch]
        $FireWallRule
    )

    begin {
        # add a temporary firewall rule if specified
        if($FireWallRule) {

            if (!([Security.Principal.WindowsPrincipal] [Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] "Administrator")) {
                Write-Output "[!] Warning: user is not an administrator, firewall rule can't be added"
                throw "[!] Warning: user is not an administrator, firewall rule can't be added"
            }

            Write-Output "[*] Setting inbound firewall rule for port: $Port"

            $FW = New-Object -ComObject hnetcfg.fwpolicy2
            $Rule = New-Object -ComObject HNetCfg.FWRule
            $Rule.Name = "Updater32"
            $Rule.Protocol = 6
            $Rule.LocalPorts = $Port
            $Rule.Direction = 1
            $Rule.Enabled = $true
            $Rule.Grouping = "@firewallapi.dll,-23255"
            $Rule.Profiles = 7
            $Rule.Action = 1
            $Rule.EdgeTraversal=$false
            $FW.Rules.Add($Rule)
        }

        if(!$Base64File) {
            [byte[]] $FileBytes = [System.IO.File]::ReadAllBytes($FilePath)
            $Base64File = [System.Convert]::ToBase64String($FileBytes)
            Write-Output "[*] Hosting file: $FilePath"
        }
        else {
            Write-Output "[*] Using base64 string file for hosting"
        }

        $WebserverScriptblock = {
            param($Port, $Base64File)

            [byte[]] $FileBytes = [System.Convert]::FromBase64String($Base64File)

            try {
                $EndPoint = New-Object System.Net.IPEndPoint([IPAddress]::any, $Port) 
                $Listener = New-Object System.Net.Sockets.TcpListener $EndPoint
                $Listener.Start() 

                # block until a TCP connection is received
                $Data = $Listener.AcceptTcpClient()

                # Write-Output "[*] Connection from: $($Data.Client.RemoteEndPoint)"
                $Stream = $Data.GetStream()

                $Stream.Write($FileBytes,0,$FileBytes.length)

                $Stream.Close()
                $Listener.Stop()
            } 
            catch [exception] {
                # Write-Output "[!] Exception: $_"
            }
        }
    }
    process {
        Write-Output "[*] Starting hosting on port: $Port"

        # start hosting the webserver
        $Null = Start-Job -Name "WebServer" -Scriptblock $WebserverScriptblock -ArgumentList $Port,$Base64File

        Start-Sleep -Seconds $ServerSleep

        # kill the webserver off
        Write-Output "[*] Killing off server"
        Get-Job -Name "WebServer" | Stop-Job

        Write-Output "[*] Server killed"
    }

    end {
        if($FireWallRule) {
            # remove the firewall rule if specified
            if($FireWallRule){
                Write-Verbose "[*] Removing inbound firewall rule"
                Write-Output "[*] Removing inbound firewall rule"
                $FW.rules.Remove("Updater32")
            }
        }
    }
}