Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 84426c2f3f9178cb…

MALICIOUS

Office (OLE) / .XLS

94.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-07-01
MD5: c1551e07c94c9c7b8409f4f9191b6c32 SHA-1: 89b101860d4adb147fcd2617034baaf41553a21a SHA-256: 84426c2f3f9178cb7171445ec6037e3affcc5abb3286b6bcc07f28ed4a36467d
200 Risk Score

Malware Insights

Emotet · confidence 95%

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

The file is an Excel 4.0 spreadsheet containing an Auto_Open macro, which is a known technique for executing malicious code. ClamAV identifies the file as Emotet, a downloader family. The macro likely executes a second-stage payload, as indicated by the 'RUN' function call within the macro sheet.

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
a9015a357d82c272296eaeaf7778ee228891238d5c9eed0b7e9705c468b7dc02
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8127 bytes