Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 59127b3982f50db0…

MALICIOUS

Office (OLE) / .XLS

216.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-11-02
MD5: d089ec8a35eaca0a6015a71f66c80cbb SHA-1: c5582d2eb71748acc2e4d4b036aa63bb777d87fa SHA-256: 59127b3982f50db065a3846377d51729786c61e32eb6f8bd5b2321847f2eee83
200 Risk Score

Malware Insights

Emotet · confidence 95%

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

The sample contains Excel 4.0 macros, specifically an Auto_Open defined name, which is a known technique for executing malicious code. ClamAV detection identifies it as 'Xls.Downloader.Emotet', indicating its function as a downloader for the Emotet family. The presence of dangerous formula APIs like RUN further supports the malicious intent.

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-b649c93692b4c9d9-9976616-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-b649c93692b4c9d9-9976616-0
  • 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
106723e9d4e5e8742cadd8ab3b3c276df9e04e9f026271b79b7247eae7a376b2
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8150 bytes