Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 9008ce6e811d83ee…

MALICIOUS

Office (OLE) / .XLS

60.0 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-09
MD5: 35c341ad133f1ce5837d3f920461e8bc SHA-1: 5b1659b2f15d0aa9153ef7a5dd91ca9f2c44895f SHA-256: 9008ce6e811d83eef7e90a2b799353a893a1cc33d08e5b60e30a869f76d9c68e
200 Risk Score

Malware Insights

Emotet · confidence 95%

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

The sample is an Excel 4.0 macro-enabled spreadsheet. Critical heuristics indicate the presence of an Auto_Open macro that utilizes dangerous functions, specifically the RUN function, to execute code. The ClamAV detection explicitly names this as Emotet. The macro sheet contains multiple URLs which are likely used 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-ea85817e7e81383e-9951566-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-ea85817e7e81383e-9951566-0
  • 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
c9424d8896eee7de77a94a4b79caaaa3c6ad54074296d7a874abf2efc9d6f719
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8352 bytes