Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 19dc079522ee3459…

MALICIOUS

Office (OLE) / .XLS

53.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-20
MD5: 83587779081de3594a3918f4cc3ecda4 SHA-1: d3fa7041786c2c4e9c566c4b1263855ed05b91bd SHA-256: 19dc079522ee34597e17e76de94a3eb72ac27252e0beee03f0a81f29a1d5cc81
200 Risk Score

Malware Insights

Emotet · confidence 95%

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

The sample is an Excel 4.0 macro-enabled spreadsheet. Heuristics indicate the presence of an Auto_Open macro that utilizes dangerous functions, specifically the RUN function. The macro constructs and executes URLs, indicating it is designed to download and execute a second-stage payload. ClamAV detection confirms this as Emotet. The reconstructed URLs are: http://colorsdrop.com/7DORfiDiAu/BquoSsU/, http://ewingconsulting.com/buy/Ewj7oYj7hYQ/, http://ceramiclafortaleza.com/css/5DSBCCH0/, and http://thuybaohuy.com/wp-content/VxhkYwH7/.

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-aa87d5786a858772-9953435-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-aa87d5786a858772-9953435-0
  • 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
7ab5ef6689937532951c996fe211a2ac046a3dbc546728bfe725212729605929
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6790 bytes