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

Static analysis result for SHA-256 0515fc098d556c30…

MALICIOUS

Office (OOXML) / .XLSM

86.8 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 14.0300
MD5: 41c81d6ca8244682b25ecc21b94886e7 SHA-1: bc8e928b07002b5e611f77e73befcde46b8d888e SHA-256: 0515fc098d556c30fb4ae81324ea5953099e0b6f9b80ece14787af94e177f25c
182 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The sample contains Excel 4.0 macros, specifically using the dangerous functions EXEC and CALL. The EXEC function appears to construct a command string from various cells, likely to download and execute a payload from one of the embedded URLs. The CALL function is also used, potentially to invoke system functions or further stages of execution. The presence of these functions and the embedded URLs strongly indicate a downloader or droppper functionality.

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

Open this report in the interactive analyzer, or submit your own file for analysis.