Emotet — Office (OOXML) / .XLSM malware analysis

Static analysis result for SHA-256 7563e52bc7f60afd…

MALICIOUS

Office (OOXML) / .XLSM

50.5 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2022-03-11
MD5: 217a1477565c7149db64b02c90bb3ecd SHA-1: c2939914b90422d55ed1d7bfb3e4276fa9d75037 SHA-256: 7563e52bc7f60afdb57757f85a2842abdc2a76a89a4fa09e593cbbb0a6f0e1ec
290 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1218.010 System Binary Proxy Execution: Regsvr32 T1105 Ingress Tool Transfer

The file is an Excel 4.0 macro-enabled spreadsheet (XLSM) containing critical heuristics indicating the use of dangerous XLM formula APIs like FORMULA, CALL, and EXEC. These are used to download and execute payloads. The embedded URLs and the explicit use of 'regsvr32.exe' in the document body strongly suggest a downloader for a second-stage payload, consistent with Emotet's behavior. The script's intent is to download and execute a payload from one of the provided URLs using regsvr32.exe.

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.Emotet03220-9941298-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet03220-9941298-0
  • 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://actividades.laforetlanguages.com/wp-admin/WQNAwrWi77MV8a05fia/
    • http://aopda.org/wp-content/uploads/KXc3Agu18w/
    • http://advogadogoiania.com.br/wp-includes/VTz0V6D/
    • https://www.agenciaigual.com.br/Novo2017/yTZMu9FxcyHYFUkb/
    • http://consejosdeorlando.com/wp-includes/mMaIlj99Y1C1sYN/
    • http://agenciaml.com.br/wp-content/lMGfW5Wk09k/
    • http://101.53.142.76/ApcCache/FiXQvn/
    • 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
b99514d31bf111baca7178f1c3b7e161c3a1df476cfbefb5ab0d85aee00a0f99
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml 4031 bytes
xlm_sheet_01.xml
57ec544c624f64a940b22b418ecc97356699a87d8f5405ae8ca128da00e7393a
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.xml 1277 bytes
xlm_sheet_02.xml
1a2bbba2a276f955ce94cee47252cbd0a00ecbdfcf526f95f8e33343bc612848
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet2.xml 1152 bytes