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

Static analysis result for SHA-256 16f1a0307b803a9e…

MALICIOUS

Office (OOXML) / .XLSM

105.5 KB Created: 2006-09-16 00:00:00 UTC Authoring application: Microsoft Excel 14.0300
MD5: a8306a0631c306438c7c0c1c249e317e SHA-1: 72d20e3710635c3f3a2bfe7225bab06172923b80 SHA-256: 16f1a0307b803a9ee8ca10d419e28e49798f1324c41343605585b652aef5f4ca
182 Risk Score

Malware Insights

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

The file is an XLSM document containing Excel 4.0 macros, which are known to be used for malicious purposes. The macros utilize dangerous functions like CALL and EXEC, indicating an attempt to download and execute a payload. The embedded URL 'https://metaflip.io/ds/3003.partsapp.com.br/ds/3003.columbia.aula-web.net/ds/3003.tajushariya.com/ds/3003.agenbolatermurah.com/ds/3003.' is highly suspicious and likely serves as the source for this payload.

Heuristics 4

  • Excel 4.0 macro sheet (1 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: CALL, EXEC, FORMULA.FILL, HALT 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 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.xml
1ac8164566eb69dad25e2fb55eafdc9b2a3eac004a1f0cc291930400a77c99df
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml 230169 bytes