Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 d6d3329f2794e99a…

MALICIOUS

Office (OLE) / .XLS

71.3 KB Created: 2022-01-20 19:00:43 Authoring application: Microsoft Excel
MD5: 313491518180167de888f7e9d46e8f57 SHA-1: 27e39a368ac5a26fd1172b05372fa9db2ed4ed08 SHA-256: d6d3329f2794e99a35585c8bf32eca703399d502908697277dcc09269588e916
140 Risk Score

Malware Insights

Emotet · confidence 95%

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

The file is an Excel 4.0 macro-enabled spreadsheet, identified by the OLE_XLM_AUTOOPEN heuristic. ClamAV detection further confirms its malicious nature, classifying it as Doc.Downloader.EmotetExcel01220-9937164-0. The presence of an Auto_Open defined name indicates that the macro will execute automatically when the workbook is opened, likely to download and execute a secondary payload, consistent with Emotet downloader behavior.

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.EmotetExcel01220-9937164-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.EmotetExcel01220-9937164-0
  • 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
7f1f89a8b36a750dced08313a4e4f056192a6eac7194357c673dbbd2670a1a18
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 4219 bytes