Office (OOXML) / .XLSX malware analysis — malicious · e305414eab40d709

MALICIOUS

Office (OOXML) / .XLSX

67.8 KB Created: 2021-03-14 19:50:37 UTC Authoring application: Microsoft Excel 16.0300

MD5: b3661e5612a5db5add9227a717927375 SHA-1: afda8973176c756c50a85ce620034658f7fe46ef SHA-256: e305414eab40d70932ba177a4beb788ff3de4a9fa81189cd5b6a46df98973cad

60 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic

The sample is an Excel file containing Excel 4.0 macros, indicated by the OOXML_XLM_MACROSHEET heuristic. The macrosheet content is heavily obfuscated and truncated, preventing a detailed analysis of its specific actions. However, the presence of Excel 4.0 macros strongly suggests an intent to execute arbitrary code, likely for malicious purposes such as downloading further payloads or establishing persistence.

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` `b2408d0b6c593d5edd3aaf5ea23f0796ace10bfc1a0a7658009a14a543f61ffe`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet1.bin	97004 bytes

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