Utils/ConvertFrom-B64ToString.ps1
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function ConvertFrom-B64ToString { <# .SYNOPSIS A PowerShell script to convert a base64 encoded string to a string. Author: Roberto Rodriguez (@Cyb3rWard0g) License: MIT Required Dependencies: None Optional Dependencies: None .DESCRIPTION Convert base64 encoded string to text. .PARAMETER B64String Base64 encoded string. .LINK https://gist.github.com/obscuresec/82775093ad892ef5fd00 https://github.com/Gerenios/AADInternals/blob/ab57903beda6d4030cedc2fd690d85caa2362b65/CommonUtils.ps1 #> [cmdletbinding()] Param( [Parameter(Mandatory = $true)] [String] $B64String ) # Replaced $Stripped = $B64String.Replace("_","/").Replace("-","+").TrimEnd(0x00,"=") # Append appropriate padding $ModulusValue = ($Stripped.length % 4) Switch ($ModulusValue) { '0' {$Padded = $Stripped} '1' {$Padded = $Stripped.Substring(0,$Stripped.Length - 1)} '2' {$Padded = $Stripped + ('=' * (4 - $ModulusValue))} '3' {$Padded = $Stripped + ('=' * (4 - $ModulusValue))} } # Decode Base64 String $Decoded = [System.Text.Encoding]::UTF8.GetString([system.convert]::FromBase64String($Padded)) $Decoded } |