Emotet — Office (OLE) / .XLSX malware analysis

Static analysis result for SHA-256 b1ee7aa00b7884ed…

MALICIOUS

Office (OLE) / .XLSX

141.4 KB Created: 2022-01-19 09:31:16 Authoring application: Microsoft Excel
MD5: c2ce0e5d4d7eb7b429e77e7bbdf09801 SHA-1: 71b41e18f5596cf7a8fcfee18679f84d536fe822 SHA-256: b1ee7aa00b7884ed02a3f5ddc07419b6e8dd6e7382269d8cc5511f06431d5eaf
140 Risk Score

Malware Insights

Emotet · confidence 95%

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

The file contains critical heuristics indicating the presence of Excel 4.0 macros, specifically an Auto_Open defined name, which is a common execution vector for Emotet. ClamAV also detected it as 'Doc.Downloader.EmotetExcel01220-9936774-0'. The macro sheet appears to be designed to execute automatically upon opening, serving as a downloader for 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
592af8991900f2f7058dc7ea90a33320ae293c7e541db4222a7b7f9c04f59d96		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8469 bytes

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