Malicious Office (OOXML) / .XLSM — malware analysis report

Static analysis result for SHA-256 0f10c56509eda514…

MALICIOUS

Office (OOXML) / .XLSM

86.8 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 14.0300
MD5: 2e9cf16a3c05bbf5e6405caac695b282 SHA-1: f54b8039b51e0e23b1f57a7795bfe2ddd529405a SHA-256: 0f10c56509eda514d026e1ef4e9200a6184b16a36a60fab62688663677c042eb
182 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1105 Ingress Tool Transfer

This Excel 4.0 macro-enabled document (XLSM) utilizes dangerous functions like EXEC and CALL to download and execute a second-stage payload. The script explicitly constructs URLs such as 'https://extendonetwork.com/puZyLuatL0W/04.html' and 'https://jarettwalen.com/vspeL07tgk5F/04.html' which are then used to fetch the payload. The use of EXEC with concatenated strings indicates a clear intent to run arbitrary code from the network.

Heuristics 4

  • Excel 4.0 macro sheet (2 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: WORKBOOK.HIDE, EXEC, CALL, HALT, 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.
  • 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://extendonetwork.com/puZyLuatL0W/04.html
    • https://jarettwalen.com/vspeL07tgk5F/04.html
    • 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
emf_00.emf
442eb38c1c88060cf62c1fd88f48f9b8961edd687fe9250cf42ff79baf20ccae
ooxml-emf OOXML EMF part: xl/media/image1.emf 296536 bytes
xlm_sheet_00.xml
e2d0c69c580969a640d565ee7f4c9f99c84cac5b5d64c997ece3e584778305c8
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.xml 1638 bytes
xlm_sheet_01.xml
bc0107a78ea6ba702702ddf8b745f24672051acbfa84cd527ab65f9785d5a729
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet2.xml 3777 bytes