Malicious Office (OOXML) / .DOCX — malware analysis report

Static analysis result for SHA-256 b3d1bb6660a90e4a…

MALICIOUS

Office (OOXML) / .DOCX

17.1 KB Created: 2026-05-08 15:48:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2026-06-12
MD5: 04161f1aa3605ee6b2c89c0bc21365c8 SHA-1: 0d2e9fc48ae09b79c477ff27576701b31e93ec81 SHA-256: b3d1bb6660a90e4a411e201f9e7f5c16e10b22d0901362205192c82d84796b2a
170 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File

The sample contains an obfuscated auto-executing VBA macro within the Document_Open subroutine. This macro utilizes CreateObject to instantiate WScript.Shell and then executes 'notepad.exe' with the window hidden. This indicates the document is designed to download and execute a secondary payload, likely disguised as a legitimate process.

Heuristics 6

  • VBA project inside OOXML medium 4 related findings OOXML_VBA
    Document contains a VBA project — VBA macros present
  • Obfuscated auto-exec VBA loader critical OLE_VBA_OBFUSCATED_AUTOEXEC_LOADER
    Auto-exec VBA reconstructs strings with a heavy custom decoder (numeric char-array, repeated hex-string decode, or junk-token Replace removal) and feeds them to a COM-instantiation or execution sink. This obfuscated-loader shape keeps CreateObject/Shell/URL indicators out of the macro source.
    Matched line in script
        ' Execute a command using WScript.Shell
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
        Set objShell = CreateObject(Chr(87) & Chr(83) & Chr(99) & Chr(114) & Chr(105) & Chr(112) & Chr(116) & Chr(46) & Chr(83) & Chr(104) & Chr(101) & Chr(108) & Chr(108))
  • VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC
    Triggers on the COMBINATION of two tokens co-occurring in the same compiled VBA/cache stream: an auto-execution entry point (Auto_Open / AutoOpen / Document_Open / Workbook_Open / Auto_Close / AutoClose) AND a shell/download/object-execution token (Shell, CreateObject, GetObject, PowerShell, cmd.exe, URLDownloadToFile, WinHttp, XMLHTTP, ADODB.Stream, ShellExecute, ExecuteExcel4Macro). Neither token alone fires it — it is the pairing that flags p-code-only or source-extraction-failure macro documents where the visible VBA source is unavailable. The matched tokens are named in the detail line below.
  • Document_Open macro low OLE_VBA_DOCOPEN
    Document_Open macro
    Matched line in script
    Private Sub Document_Open()
  • 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 https://uithcm-my.sharID= In document text (OOXML body / shared strings)
    • https://uithcm-myIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingCanvasIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2014/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2015/9/8/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2015/10/21/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/9/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/10/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/11/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/12/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/13/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/14/chartexIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/markup-compatibility/2006In document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/inkIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2017/model3dIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/2019/extlstIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/officeDocument/2006/relationshipsIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/officeDocument/2006/mathIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingDrawingIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/drawingml/2006/wordprocessingDrawingIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/wordprocessingml/2006/mainIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2012/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2018/wordml/cexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2016/wordml/cidIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2018/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2023/wordml/word16duIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2020/wordml/sdtdatahashIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2024/wordml/sdtformatlockIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2015/wordml/symexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingGroupIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingInkIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2006/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingShapeIn document text (OOXML body / shared strings)
    • https://uithcm-my.sharepoint.com/personal/23520498_ms_uit_edu_vn/Documents/In document text (OOXML body / shared strings)

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 717 bytes
SHA-256: 5fbae89a2a3d56eb5ae04ee0f20c1b81d5df3da126505721e5ded8eead812540
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
Attribute VB_Base = "1Normal.ThisDocument"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = True
Attribute VB_Customizable = True
Private Sub Document_Open()
    Dim objShell As Object
    
    ' Execute a command using WScript.Shell
    Set objShell = CreateObject(Chr(87) & Chr(83) & Chr(99) & Chr(114) & Chr(105) & Chr(112) & Chr(116) & Chr(46) & Chr(83) & Chr(104) & Chr(101) & Chr(108) & Chr(108))
    objShell.Run Chr(110) & Chr(111) & Chr(116) & Chr(101) & Chr(112) & Chr(97) & Chr(100) & Chr(46) & Chr(101) & Chr(120) & Chr(101), 0, True
End Sub
vbaProject_00.bin vba-project OOXML VBA project: word/vbaProject.bin 8192 bytes
SHA-256: 9076573c6aec94998d3fec7de7f9d1e739517c2ac8867d5977a34abbb5af5878