Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 34347e1f2bae42d0…

MALICIOUS

Office (OLE) / .XLS

80.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-15
MD5: 78cc938396332b501368d5b37750a488 SHA-1: 9f7fca3a021eec41363f01b5653458e9dc3379c4 SHA-256: 34347e1f2bae42d0377f6a71e04919c30acb9ba0f030d94b723e8d46d30a346c
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 entry, which is a known technique for executing malicious code. The macros construct URLs that are likely used to download and execute a second-stage payload. ClamAV detection further confirms its malicious nature, identifying it as Emotet.

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
2fdf21f2db447f9be93416b81af1c740576c18d6efe5c8c6f3d215a65c941f1d
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6790 bytes