Emotet Office (OLE) / .XLSX malware analysis — malicious · 48fee052f0fa5361

MALICIOUS

Office (OLE) / .XLSX

70.7 KB Created: 2022-01-20 19:00:43 Authoring application: Microsoft Excel

MD5: 4ebe46b6d33d9b93111448da218650d4 SHA-1: a5fb86134455060541b3a6039aae10dd197cc4cd SHA-256: 48fee052f0fa5361ddc892d4768321a00e5c80adabc60654488ea8fc1ffa135f

140 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK

T1059.005 Visual Basic for Applications T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV with the signature Doc.Downloader.EmotetExcel01220-9937164-0, indicating a known Emotet downloader variant. Crucially, the presence of an Excel 4.0 macro sheet with an Auto_Open defined name confirms that the spreadsheet is designed to automatically execute embedded XLM macros when opened. This is a common delivery mechanism for Emotet, which uses such macros to download and execute further stages of the malware.

Heuristics 3

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.
ClamAV: Doc.Downloader.EmotetExcel01220-9937164-0 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Doc.Downloader.EmotetExcel01220-9937164-0
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.

Filename	Kind	Source	Size
`xlm_macros.txt` `7f1f89a8b36a750dced08313a4e4f056192a6eac7194357c673dbbd2670a1a18`	xlm-macro	oletools.olevba.extract_all_macros (XLM macro listing)	4219 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.