How to Apply Encrypt/Decrypt in Powershell? - windows

Question

Im using in PS the next command:
"Password" | ConvertTo-SecureString -AsPlainText -Force | ConvertFrom-SecureString
This generate a Key that im saving as "Key.txt" file
Now i want to decrypt that password using this:
$password = Get-Content password.txt (or just copy-pasting the key)
$cred = New-Object -TypeName System.Management.Automation.PSCredential -argumentlist $username,($password | ConvertTo-SecureString)
BUT...
how i supose to add that to this...
$EmailFrom = "MyMail#gmail.com"
$EmailTo = "MayMail#gmail.com"
$Subject = "Test"
$Body = "this is a Test"
$SMTPServer = "smtp.gmail.com"
$SMTPClient = New-Object Net.Mail.SmtpClient($SmtpServer, 587)
$SMTPClient.EnableSsl = $true
$SMTPClient.Credentials = New-Object System.Net.NetworkCredential("My_USer", "My_Password");
$SMTPClient.Send($EmailFrom, $EmailTo, $Subject, $Body)
I want to add it as My_Password, of course i should add a variable $password that comes from the Key.txt file for example, but then...?

Answer 1

Nope, storing in plain text is not good at all, but if you are not concerned about that then it's there.
You have other options, with secure / encrypted files and Windows CredMan:
Quickly and securely storing your credentials – PowerShell
To get a credential object we can either manually create one or use the Get-Credential cmdlet to prompt for the account details:
$Credential = Get-Credential
To store the credentials into a .cred file:
$Credential | Export-CliXml -Path "${env:\userprofile}\Jaap.Cred"
And to load the credentials from the file and back into a variable:
$Credential = Import-CliXml -Path "${env:\userprofile}\Jaap.Cred"
Invoke-Command -Computername 'Server01' -Credential $Credential {whoami}
Securely Store Credentials on Disk
Allow multiple users to access credentials stored using export-clixml
How to run a PowerShell script against multiple Active Directory domains with different credentials
PowerShell Credentials Manager
CredMan.ps1 is a PowerShell script that provides access to the Win32 Credential Manager API used for management of stored credentials.
https://gallery.technet.microsoft.com/scriptcenter/PowerShell-Credentials-d44c3cde
And modules to use
https://powershellgallery.com/packages/BetterCredentials
https://powershellgallery.com/packages/CredentialManager
https://powershellgallery.com/packages/IntelliTect.CredentialManager

Answer 2

First we save the credentials
"Password123" | ConvertTo-SecureString -AsPlainText -Force | ConvertFrom-SecureString | Out-File C:\key.txt -NoNewline
Then we can use it just like this :
$SMTPClient = New-Object Net.Mail.SmtpClient("SomeServer", 587)
$SMTPClient.Credentials = New-Object -TypeName System.Management.Automation.PSCredential -argumentlist ThisIsAUserName ,($(Get-Content C:\key.txt) | ConvertTo-SecureString)
And we can check to make sure it loaded correctly like this :
$SMTPClient.Credentials | select username, password
The output looks like this
UserName Password
-------- --------
ThisIsAUserName Password123