Malicious Office (OLE) / .XLSX — malware analysis report

Static analysis result for SHA-256 0d8883dd2e6743af…

MALICIOUS

Office (OLE) / .XLSX

129.5 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: b25c0a6ba54a980a5bce4e0e7c0cc6d9 SHA-1: 8f34dda9b40c78b5d2733cea240e59391b5f3b85 SHA-256: 0d8883dd2e6743aff6ef9f575d12aa5e9b9c0f8441c069d34def61aba18bf22d
300 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1105 Ingress Tool Transfer

The sample contains obfuscated VBA macros, including a Workbook_Open auto-execution routine, which is a common loader technique. The script attempts to create a Wscript.Shell object to execute commands, specifically downloading and running a VBS file from a hardcoded URL. The reconstructed URL is 'http://fulleyness-safety.com/--/P6x/4Za/', which is indicative of a downloader payload.

Heuristics 7

  • Obfuscated auto-exec VBA loader critical OLE_VBA_OBFUSCATED_AUTOEXEC_LOADER
    Auto-exec VBA reconstructs strings with a heavy custom decoder (numeric char-array, repeated hex-string decode, or junk-token Replace removal) and feeds them to a COM-instantiation or execution sink. This obfuscated-loader shape keeps CreateObject/Shell/URL indicators out of the macro source.
  • ClamAV: Doc.Downloader.EmotetRed02220-9938909-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.EmotetRed02220-9938909-0
  • Reference to Windows Script Host high SC_STR_WSCRIPT
    Reference to Windows Script Host
  • Workbook_Open macro high OLE_VBA_WBOPEN
    Workbook_Open macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
  • 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.
  • VBA macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
7a075e02dc1e88807280b9b84946715e79a3c091d50391301434649c77b78ea1
vba-macro oletools.olevba.extract_macros (decoded VBA source) 12808 bytes