Office (OOXML) / .XLSX malware analysis — malicious · af7015aa503a6ee7

MALICIOUS

Office (OOXML) / .XLSX

224.7 KB Created: 2021-08-16 09:36:27 UTC Authoring application: Microsoft Excel 12.0000

MD5: 6e0693d6908bd5f3b096a2e345464bf2 SHA-1: 5e2c71e9afbcaf318f1b582f8af2bd58409013c5 SHA-256: af7015aa503a6ee762e11b6858966afd6593ed2cf9ca4ce6f13297d976616c82

60 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic

The primary heuristic indicates the presence of Excel 4.0 macros within the XLSX file. While the macro content is truncated and heavily obfuscated, the presence of such macros strongly suggests an intent to execute arbitrary commands, a common technique for initial access or payload delivery. Without further deobfuscation or network indicators, the specific family and full attack chain remain unclear.

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` `63d236433d8b2a1a370469c42d0d98a5c81064f5bdacc62c0ea6d587dc6c41d9`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet1.bin	390933 bytes

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