Emotet — Office (OLE) / .XLSX malware analysis

Static analysis result for SHA-256 0fa0678d3405e38a…

MALICIOUS

Office (OLE) / .XLSX

121.0 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: 43896adf9851803ad4b4b940f907f155 SHA-1: 991ee0156e2d4e575dc1a56494f8820fd6feccee SHA-256: 0fa0678d3405e38aee40b7ae71dc70da0364404b5db4031c25775e4091a24f45
302 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment T1105 Ingress Tool Transfer

The sample is an Excel file containing VBA macros, specifically a Workbook_Open event that triggers execution. Heuristics indicate the macro is designed to download payloads from multiple URLs, and ClamAV identifies it as Emotet. The macro attempts to construct and execute commands involving downloaded VBS and BAT files, likely to establish persistence and download further stages.

Heuristics 8

  • URL reconstructed from VBA cell-staged base64 dropper (7 URLs) critical OLE_VBA_CELL_DROPPER_URL
    VBA reads worksheet cells, strips junk substrings via Replace(), and base64/UTF-16 decodes the result into a PowerShell EncodedCommand payload. The download URL is never contiguous in the file bytes; it was recovered by removing the macro's Replace() junk tokens from the cell strings and decoding the staged base64.
  • ClamAV: Xls.Downloader.Emotet-ab81c42b2bd4747e-9951196-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-ab81c42b2bd4747e-9951196-0
  • 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
  • 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 http://lbsbriefs.com/cgi/2kl8X826xEKeuhI/
    • http://howebeautiful.com/eln-images/tyj208/
    • http://lazylargomotels.com/cgi/wZrYbJ/
    • http://sleepstarlite-ozark.com/batesville/UjX/
    • http://osaka.musicaldog.com/05-set/YLBOd/
    • https://egemenrulman.com/Fox-C404/qrr2OCShGJGH06Gm/
    • http://skyridgedesigns.com/eln-images/38pr2cu3xt2Ai/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
faf50200d5a9adeeda00cc1da1bbf8f6abf0317a1e97a58db8ae804ba12ba446
vba-macro oletools.olevba.extract_macros (decoded VBA source) 13985 bytes