Emotet — Office (OLE) / .XLSX malware analysis

Static analysis result for SHA-256 b9ef162c94e059a2…

MALICIOUS

Office (OLE) / .XLSX

95.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-07-11
MD5: d4444f246212507b6e3d4506573e9ea9 SHA-1: f64a46d45ba76d2582507e07c175e98b90c40e96 SHA-256: b9ef162c94e059a27f6c5e0950ddbd673a3bb2c82c7e9c914fe73b3355e1bdce
200 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File

The file contains Excel 4.0 macros, specifically an Auto_Open macro, which is a known technique for executing malicious code. ClamAV detection explicitly identifies it as an Emotet downloader. The macro uses the RUN function, indicating it's designed to download and execute a second-stage payload.

Heuristics 4

  • 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.
  • XLM Auto_Open with dangerous formula APIs critical OLE_XLM_DANGEROUS_FN
    Excel 4.0 macro sheet contains an Auto_Open / Auto_Close entry and dangerous XLM formula APIs that can invoke programs, write files, or transfer control without VBA.
  • ClamAV: Xls.Downloader.Emotet-ea81817e7f807ab1-9952142-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-ea81817e7f807ab1-9952142-0
  • 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
85773188e79d904ef8ecf815a27f3a8200cc87e1822ab4901cc9bed29c53e636		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8156 bytes

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