Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 c2550bccc47349c3…

MALICIOUS

Office (OLE) / .XLS

60.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-16
MD5: 7322c56e0d30744c6788abc1f4290ae0 SHA-1: 7c22cb2237ed1d45c1f85ffe901c8135d98d23be SHA-256: c2550bccc47349c35350721892f30ff54338314e11ef8b7d06434ae2632b5542
200 Risk Score

Malware Insights

Emotet · confidence 95%

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

The sample is an Excel 4.0 macro-enabled spreadsheet detected as Emotet by ClamAV. The XLM macros contain an Auto_Open function that utilizes dangerous API calls, specifically the RUN function, to download a payload from one of the provided URLs. The presence of the Auto_Open defined name and the use of the RUN function strongly indicate a downloader's behavior.

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-ea85817e7e81383e-9951566-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-ea85817e7e81383e-9951566-0
  • 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
d77c0e98c974009fe5584bce5e0ffd72a8b15ac4e83c1240090b3dfbcca2aa7b
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8320 bytes