Office (OOXML) / .XLSX malware analysis — malicious · ee88089aec2e4691

MALICIOUS

Office (OOXML) / .XLSX

120.1 KB Created: 2021-03-29 19:54:15 UTC Authoring application: Microsoft Excel 16.0300

MD5: 914a8c103bdada8d5f56afdac0b80667 SHA-1: 1e8240abb67d2f7793c0d4a1f3d51f45038c8d9a SHA-256: ee88089aec2e4691ed02144d4284ca98520d87ddd5b59bc4031a63c036101344

60 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic

The file is an Excel spreadsheet containing embedded Excel 4.0 macros. The heuristic firing indicates the presence of these macros, which are often used to download and execute malicious payloads. The script content is heavily obfuscated and truncated, preventing a detailed analysis of its specific actions or the reconstruction of any URLs or commands. Therefore, the exact attack vector and family remain unknown.

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` `d949a8b7ffa97589188bab8170d521758076d1b4c068e080055a6adbc7dea520`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet1.bin	98782 bytes

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