Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 92e0b751397367a0…

MALICIOUS

Office (OLE) / .XLS

95.0 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-07-06
MD5: 691df3395ae0a408899becc1a28097ec SHA-1: 8d1a6bc3d920b9fa245b004ebf48e933a462253a SHA-256: 92e0b751397367a06b0a113f2572c7bddfde6f95006cadbc6f6967d6a292c6ce
200 Risk Score

Malware Insights

Emotet · confidence 95%

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

The file contains Excel 4.0 macros, specifically an Auto_Open defined name, which is a known technique for executing malicious code. ClamAV identifies this as an Emotet downloader. The macro uses the RUN function, indicating it likely downloads and executes a second-stage payload.

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
084b5f7ef3fea0b6fe02d0274a37b6184cd15657f9606658d7a9c58e6ff42b9a
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8159 bytes