Emotet — Office (OOXML) / .XLSM malware analysis

Static analysis result for SHA-256 8f18344b57dce725…

MALICIOUS

Office (OOXML) / .XLSM

32.7 KB Authoring application: Microsoft Excel 16.0300 First seen: 2022-04-01
MD5: ebc28c1103ca334d31812b99e36e5c44 SHA-1: 218fc75be9a3499cf8e867fe172161e3154e0397 SHA-256: 8f18344b57dce7256dca7f7aaa28da000a7195bff2747dd12a89cac763f49aef
258 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 PowerShell T1059.001 PowerShell T1204.002 Malicious File T1105 Ingress Tool Transfer

The file is an XLSM document containing Excel 4.0 macros, identified by the 'OOXML_XLM_MACROSHEET' and 'OOXML_XLM_DANGEROUS_FN' heuristics. The macros are designed to download a payload from one of the embedded URLs, such as 'https://www.doh-designsection.com/Files/LXZv9wBqLH/', and save it as '..\xewn.dll'. The 'OOXML_XLM_AUTOOPEN_DEFINEDNAME' heuristic indicates that the macro is likely executed automatically upon opening the document. The ClamAV detection as 'Xls.Downloader.Emotet04220-9942581-0' strongly suggests the Emotet family.

Heuristics 7

  • Excel 4.0 macro sheet (1 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.Emotet04220-9942581-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet04220-9942581-0
  • External hyperlinks (1) low OOXML_EXTERNAL_HYPERLINKS
    Document contains 1 external hyperlink — clickable URLs are stored as external relationships. First target: http://www.centurypapers.com/database-wordpres/VDYOi/
  • Hidden worksheet (hidden) low OOXML_HIDDEN_SHEET
    Excel workbook contains 7 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 https://www.doh-designsection.com/Files/LXZv9wBqLH/
    • http://draheimdesign.com/allyears_jdrf_video/DZEUcZ5/
    • http://dunyaaslan.com/cgi-bin/IwvOXl/
    • https://www.centurypapers.com/database-wordpres/VDYOi/
    • http://fontecmobile.com/pk/tRqU7/
    • http://dusangerzicgera.com/img/4v7QHP/
    • http://www.centurypapers.com/database-wordpres/VDYOi/
    • 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.xml
4153191ccbeaead436d640cd9bad7b4c39fa54474c8ec9a17be8e3e4600146ed
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml 3602 bytes