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

Static analysis result for SHA-256 6ac436660eb258f7…

MALICIOUS

Office (OOXML) / .XLSM

109.5 KB Created: 2006-09-16 00:00:00 UTC Authoring application: Microsoft Excel 14.0300
MD5: d2f1c2791b86b9bb29d61f9924f79ea7 SHA-1: d9b11766790bad414510da9b749d2b75fc80a903 SHA-256: 6ac436660eb258f7d1ae6f4aebe098b4a8ff3b660aa47ccb087ed2112e2ffae3
210 Risk Score

Malware Insights

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

This XLSM file contains Excel 4.0 macros, including an Auto_Open defined name, which is a strong indicator of malicious intent. The macros utilize dangerous functions like EXEC to call external code, specifically referencing '..\duron.bnm1' and '..\duron.bnm2' which suggests the execution of downloaded payloads. The embedded URLs point to external resources likely hosting these payloads, indicating a downloader pattern.

Heuristics 6

  • 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: EXEC, HALT, FORMULA, WORKBOOK.HIDE, CALL 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.
  • Suspicious extracted artifact medium EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • Hidden worksheet (hidden) low OOXML_HIDDEN_SHEET
    Excel workbook contains 1 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://shapoorjipallonji.online/drms/ind.html
    • https://studio.joellemagazine.com/drms/ind.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.xml
477aeccaaa162efd32bb8acf28c472f6c70359e46f59213b79e20f048af0f34f
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet2.xml 3528 bytes
xlm_sheet_01.xml
9f930289e13f67da399b0aeb5dc75db9b6d9febed2d1afb324c89cca03dce6a5
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml 205645 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 shell/COM execution token(s).