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

Static analysis result for SHA-256 199fc0137aa2a7e6…

MALICIOUS

Office (OOXML) / .XLSM

109.5 KB Created: 2006-09-16 00:00:00 UTC Authoring application: Microsoft Excel 14.0300
MD5: ce7100e769f893b73d892de0ffa40d0e SHA-1: 69b311f8f3e972a2cef643757dbe08a0358b2b0e SHA-256: 199fc0137aa2a7e672f1c1d3097e3ca75020e2d3c12623703fac387777b9ac06
210 Risk Score

Malware Insights

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

This Excel macro-enabled spreadsheet (XLSM) utilizes Excel 4.0 macros, which are known for their ability to execute arbitrary code. The macros contain calls to dangerous functions like EXEC and CALL, and reference URLs that are likely used to download and execute a second-stage payload. Specifically, the formula `=EXEC(Sheet2!AM34&"..\duron.bnm1",DllRegisterServer)` indicates an attempt to execute a file, likely a DLL, from a relative path. The embedded URLs `https://shapoorjipallonji.online/drms/ind.html` and `https://studio.joellemagazine.com/drms/ind.html` are strong indicators of a download source.

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).