Office (OOXML) / .XLSX malware analysis — malicious · 87086d5ad9c8a0dd

MALICIOUS

Office (OOXML) / .XLSX

249.6 KB Created: 2021-10-10 18:55:08 UTC Authoring application: Microsoft Excel 12.0000

MD5: c35296bd615bb0260ec444fb6917c2d7 SHA-1: f2db011b1642bbc44ad53b45b1bb73ce3568334e SHA-256: 87086d5ad9c8a0ddc1bb7f656d6002299bec033daa098899c91c258e3f310359

60 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic

The file is an Excel spreadsheet containing Excel 4.0 macros, indicated by the OOXML_XLM_MACROSHEET heuristic. The macrosheet content is heavily truncated, preventing a detailed analysis of its specific actions. However, the presence of Excel 4.0 macros strongly suggests an attempt to execute arbitrary commands or download further payloads.

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.

Filename	Kind	Source	Size
`xlm_sheet_00.bin` `3e5d3a3560c46aef2bebce1dfd0f3abcfae005546fa6378fdbb526b3c249354e`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet1.bin	586358 bytes

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