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

Static analysis result for SHA-256 8fa515dc6b66c78a…

MALICIOUS

Office (OOXML) / .XLSX

58.7 KB Created: 2021-10-27 10:31:49 UTC Authoring application: Microsoft Excel 12.0000
MD5: 80147b536f249fe57df7b80bf0c59e28 SHA-1: 4cdc8d2d7e0369091ddc2e925b93aff1c682a132 SHA-256: 8fa515dc6b66c78a8d62c8190614353427eed2bbbad8f81c5c9ccbc0fff8b85b
60 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic

The sample is an Excel file containing embedded Excel 4.0 macros, indicated by the OOXML_XLM_MACROSHEET heuristic. These macros are designed to execute arbitrary code, likely to download and run a second-stage payload. The reconstructed path 'C:\ProgramData\excel.rtf' suggests a potential dropped file or staging location.

Heuristics 1

  • 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. The macro sheet is stored as XLSB/BIFF12 binary content, which many XML-only OOXML scanners miss.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.bin
60aa49f47923fc8cc3972c6237e9b371bdfd33d1f19992c08150ed3f2e2be786		 xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.bin 99179 bytes

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