Malicious Office (OLE) / .XLS — malware analysis report

Static analysis result for SHA-256 c81a09fe8d5421fa…

MALICIOUS

Office (OLE) / .XLS

80.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-16
MD5: 8680595d1328f33331e6facbf8a4fcb1 SHA-1: 972d9c43f7ec5ba1879920f58765889888fe1374 SHA-256: c81a09fe8d5421fa1dd7b0935c02c7d7ff763c3623ae237a8a046482079c961e
200 Risk Score

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