Emotet — Office (OOXML) / .XLSX malware analysis

Static analysis result for SHA-256 10a92107eb104b74…

MALICIOUS

Office (OOXML) / .XLSX

237.2 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2022-03-10
MD5: 5ac6de11d08aa8e38d80b373b32ea197 SHA-1: 00c780cc44d682896a2349259fbbfc9536875e12 SHA-256: 10a92107eb104b74448bbac4cf8b0b0b7ca531a10b5c1ca37b93ef995f686319
120 Risk Score

Malware Insights

Emotet · confidence 95%

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

The file was detected as malicious by ClamAV with the signature 'Xls.Downloader.Emotet-OOXML_XL-af43432fbcb8603c-9980048-0'. Static analysis revealed the presence of Excel 4.0 macro sheets, which are commonly used to download and execute secondary payloads. The heuristic firings and the ClamAV signature strongly suggest this is a downloader variant of the Emotet family.

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
e7085ac4bb151e06e68b0fa03406a3caeb756afa2ad3891a5e6a51326a913a61		 xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.bin 2466 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.