Emotet — Office (OLE) / .XLSX malware analysis

Static analysis result for SHA-256 9a0279149641144e…

MALICIOUS

Office (OLE) / .XLSX

141.4 KB Created: 2022-01-18 14:11:14 Authoring application: Microsoft Excel
MD5: bd3a0f78e83c88b39c57c4552533fcfa SHA-1: 30aba58de88142e9b43c8aee3fd7adf523d05231 SHA-256: 9a0279149641144e4f3152072a4a9b108c98cf39d6deb7471c49736711635507
140 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.005 Visual Basic

The critical heuristics indicate the presence of an Excel 4.0 macro sheet with an Auto_Open defined name, a common technique for Emotet. ClamAV also specifically detected this file as 'Doc.Downloader.EmotetExcel01220-9936774-0'. The Auto_Open macro is designed to execute malicious code automatically when the spreadsheet is opened, likely to download and execute a second-stage payload.

Heuristics 3

  • Excel 4.0 Auto_Open defined name critical OLE_XLM_AUTOOPEN_DEFINEDNAME
    oletools recovered an Auto_Open / Auto_Close entry from an Excel 4.0 macro sheet. The raw BIFF name can be tokenized or partially opaque to byte-string checks, but the recovered macro listing confirms the workbook has an XLM auto-execution entry.
  • ClamAV: Doc.Downloader.EmotetExcel01220-9936774-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.EmotetExcel01220-9936774-0
  • Excel 4.0 (XLM) macro sheet present medium OLE_XLM_AUTOOPEN
    Workbook contains an Excel 4.0 macro sheet sub-stream — XLM is rarely seen in modern legitimate workbooks and was a major Office malware vector during 2020-2022.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
c355a4e8b51815f97cf3e202ab7d47ce16f5f701c419b0e7a11ef751a8ea709e		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 3661 bytes

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