Emotet — Office (OOXML) / .XLSM malware analysis

Static analysis result for SHA-256 2e53df694773f712…

MALICIOUS

Office (OOXML) / .XLSM

44.7 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2022-03-10
MD5: 6abd98978320ed884472a679a93ee7c9 SHA-1: 23740c4351694cca1c516a9c9e915924cac7c6ea SHA-256: 2e53df694773f7121f1e14a449fbbc686fbedf2e01520d34e8ce40dbae8debd8
290 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1218.011 Signed Binary Proxy Execution: Rundll32 T1059.001 PowerShell T1105 Ingress Tool Transfer

The sample is an XLSM file containing Excel 4.0 macros, which are known to be used for malicious purposes. The macros utilize dangerous API functions like FORMULA to download and execute payloads. Specifically, the macros construct commands involving 'regsvr32.exe' and URLs such as 'https://lifebotl.com/Response/WllkQWM/' to fetch and run a second-stage payload. The ClamAV detection as 'Xls.Downloader.Emotet' further supports the Emotet family attribution.

Heuristics 7

  • 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.
  • Excel 4.0 Auto_Open defined name critical OOXML_XLM_AUTOOPEN_DEFINEDNAME
    Workbook defines _xlnm.Auto_Open or _xlnm.Auto_Close while containing an XLM macro sheet. This is the OOXML/XLSB auto-execution shape for Excel 4.0 macros.
  • Dangerous XLM formula APIs: FORMULA critical OOXML_XLM_DANGEROUS_FN
    Excel 4.0 macro sheet uses formula APIs that call directly into Win32 (=CALL/=EXEC/=REGISTER/=FORMULA). These are the primitives used to download payloads, write files, and start processes from an XLM macro without invoking VBA.
  • ClamAV: Xls.Downloader.Emotet03221-9941289-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet03221-9941289-0
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • Hidden worksheet (hidden) low OOXML_HIDDEN_SHEET
    Excel workbook contains 6 hidden sheet(s) — hidden sheets are commonly used to conceal macro code, staging data, or intermediate payload construction
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.agretto.com/Template/ziasuz5w8pS08Gm2/
    • https://lifebotl.com/Response/WllkQWM/
    • http://185.187.70.35/wordpress_bo/srvoaI2MBFc/
    • http://103.85.95.5/v1/uploads/87DtpAEZULSccOn/
    • http://www.agnesleung.com/raw.backup/j4ry/
    • https://livejagat.com/h/SjpRvD/
    • http://188.166.245.112/sipadu/eFi8UiJETZiK1FB/
    • http://schemas.openxmlformats.org/spreadsheetml/2006/main
    • http://schemas.microsoft.com/office/excel/2006/main
    • http://schemas.openxmlformats.org/officeDocument/2006/relationships
    • http://schemas.openxmlformats.org/markup-compatibility/2006
    • http://schemas.microsoft.com/office/spreadsheetml/2009/9/ac
    • http://schemas.microsoft.com/office/spreadsheetml/2014/revision
    • http://schemas.microsoft.com/office/spreadsheetml/2015/revision2
    • http://schemas.microsoft.com/office/spreadsheetml/2016/revision3
    • http://schemas.microsoft.com/office/spreadsheetml/2016/revision6

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.xml
aa639861ddc5b5835fc6dc55f810a8cdd345d5a0f25a9228a1e87fb64257685f
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml 4348 bytes
xlm_sheet_01.xml
ff04c6af5f59c8590aa4a7b71a1b2742e5c5b487ad6a63ca1d90a970ae623c5f
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.xml 1277 bytes
xlm_sheet_02.xml
33ff727dfe6d455b4500b1331dbc121c2312bb4ec71c24948d23118c341dc852
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet2.xml 1213 bytes