Office (OOXML) / .XLSX malware analysis — malicious · 1e8b2960094c9962

MALICIOUS

Office (OOXML) / .XLSX

113.6 KB Created: 2021-03-05 04:08:28 UTC Authoring application: Microsoft Excel 16.0300

MD5: 8ff9c60973030bf70c51629affbb8141 SHA-1: 0ab1fd731a256bdc25fa12f5290613e30623a6dc SHA-256: 1e8b2960094c99626ed8409067304e8f2f3f9b623f056a2551c72b7742979720

120 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic

The file is an Excel document containing Excel 4.0 macros, as indicated by the OOXML_XLM_MACROSHEET heuristic. The ClamAV detection further confirms its malicious nature as a downloader. While the macro content is truncated, the presence of Excel 4.0 macros strongly suggests an intent to download and execute a secondary payload, a common technique for malware delivery.

Heuristics 2

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.
ClamAV: Doc.Downloader.Trojan-bf70f023603538ee-bf70f023603538ee-9950269-0 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Doc.Downloader.Trojan-bf70f023603538ee-bf70f023603538ee-9950269-0

Extracted artifacts 1

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`xlm_sheet_00.bin` `39981504ac2d545f2268e4fe450e18f521d1fe55f49ff6e02d2b699d60bb2ec1`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet1.bin	10168 bytes

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