Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 e5d02035a862b7d1…

MALICIOUS

Office (OLE) / .XLS

70.0 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-05-04
MD5: cc19c7dae0f0a038c95d3b77ba66bf8e SHA-1: 7fb7e465ffa490c5b3d8ffda0f4c34a7f3b9eff3 SHA-256: e5d02035a862b7d1bfd261318bbd2f48601dd61248b6840a125bd0d1546c2ec4
200 Risk Score

Malware Insights

Emotet · confidence 95%

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

The critical heuristics indicate the presence of Excel 4.0 macros, specifically an Auto_Open function that utilizes dangerous APIs like RUN. The extracted URLs suggest the macro is designed to download and execute a second-stage payload, consistent with Emotet's typical behavior. The ClamAV detection further supports the Emotet family attribution.

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-b3c5cc3b13c03bcc-9950246-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-b3c5cc3b13c03bcc-9950246-0
  • 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
023eece581745d86e8a881663e496cab25dc20dc1e2c24ba47f1be10064b9c6f
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6827 bytes