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

Static analysis result for SHA-256 79a215984dea40c9…

MALICIOUS

Office (OOXML) / .XLSM

86.8 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 14.0300
MD5: 77bdca916c98754475d1e1fd196ee8d0 SHA-1: 414b9131721d05e0b8824f3e8116eb8fa023ab50 SHA-256: 79a215984dea40c949f6422839a08998ab5f4fb3a6f427e6a87d403e90277f5f
182 Risk Score

Malware Insights

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

The file contains Excel 4.0 macros, specifically using the dangerous functions EXEC and CALL to download and execute a second-stage payload. The macro attempts to construct a URL from various cells, likely pointing to one of the identified malicious domains. The use of EXEC and CALL functions directly invokes Win32 APIs, bypassing VBA and enabling direct execution of downloaded content.

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://thersnyc.com/fxcS6exSJr0/04.html
    • https://justverify.online/ZKrubZZn5V/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
8877d538d505af08b0c326ee597bc05eb27a221881758da594814f19457722a4
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet2.xml 3709 bytes