PowerShell: convert a SecureString to a String

Sometimes I need to use a SecureString but then I’m forced to use that string in a non-secure way. Although the recommendation is not to do this, the reality is that there are many scenarios where it’s necessary. A simple example is when I need the user to enter sensitive data in the console, but then I need to use that data as plain text to pass it as a parameter to a Windows executable. This is an example of how to do it:

Param(
   [Parameter(Mandatory=$True)]
   [SecureString]$password
)

function Decrypt-SecureString($secureString) {
    $BSTR = [System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($password)
    return [System.Runtime.InteropServices.Marshal]::PtrToStringAuto($BSTR)
}

$nonSecure = Decrypt-SecureString $password