Emotet — Office (OOXML) / .XLSX malware analysis

Static analysis result for SHA-256 5b777785f638b272…

MALICIOUS

Office (OOXML) / .XLSX

233.8 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2022-03-10
MD5: c33e8ea3f9b057a000c0bf4b603297a7 SHA-1: 3036b5a4f0ca84fbf6df6bfc24f8e8affd8b530e SHA-256: 5b777785f638b27254030c85cc845e9807c68db142c457495362723865489d41
120 Risk Score

Malware Insights

Emotet · confidence 95%

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

The sample was detected as Emotet by ClamAV and exhibits critical heuristic firings for Excel 4.0 macros. The embedded XLM macros are designed to download and execute a secondary payload, a common Emotet tactic. The specific detection name indicates a downloader functionality.

Heuristics 2

  • Excel 4.0 macro sheet (3 sheet(s)) critical OOXML_XLM_MACROSHEET
    Spreadsheet contains an Excel 4.0 (XLM) macro sheet — XLM was a major Office malware vector during 2020-2022 and evaded many VBA-focused controls before Microsoft tightened XLM defaults. Even legitimate XLM use is rare in modern workbooks. The macro sheet is stored as XLSB/BIFF12 binary content, which many XML-only OOXML scanners miss.
  • ClamAV: Xls.Downloader.Emotet-OOXML_XL-af43432fbcb8603c-9980048-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-OOXML_XL-af43432fbcb8603c-9980048-0

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.bin
ba41a11b1be4eaa156bff86597ea809a971edc4d801f70a4529d6d84b93c19c0		 xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.bin 2469 bytes
xlm_sheet_01.bin
294fba96533e16b8e32fcc670b890c44fe9dfc759e5d84743c74026ba7bd4a20		 xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.bin 428 bytes
xlm_sheet_02.bin
f0daf3cbff097906d4170f35f5f5c2394e9b70d2a487782035c708617ae7b9ec		 xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet2.bin 428 bytes

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