Emotet — Office (OLE) / .XLSX malware analysis

Static analysis result for SHA-256 589ddde0af250536…

MALICIOUS

Office (OLE) / .XLSX

143.0 KB Created: 2022-01-26 02:21:30 Authoring application: Microsoft Excel
MD5: daab0fe3935632b685bd5a5afa948e39 SHA-1: 404979b6cf3bead4762c151e64f1c3b4bbf15291 SHA-256: 589ddde0af250536e9a84ea25a737e09c4889b5a4b623cf1e45327504f5b5673
200 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Service Execution: Service Control T1566.002 Phishing: Spearphishing Attachment

The file contains Excel 4.0 macros, specifically an Auto_Open macro, which is a known technique for executing malicious code. The ClamAV detection explicitly names this as an Emotet downloader variant. The macro's use of dangerous formula APIs, such as RUN, indicates it is designed to execute arbitrary commands.

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-bd646319c2d29cd6-9951195-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-bd646319c2d29cd6-9951195-0
  • 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
46284ea41c691066b9fe85a87bc7e9bfc77336182ea3b4ed700574b0c8cd3189
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 3141 bytes