Office (OOXML) / .XLSX malware analysis — malicious · 66705441f12de8be

MALICIOUS

Office (OOXML) / .XLSX

65.6 KB Created: 2021-03-15 18:25:26 UTC Authoring application: Microsoft Excel 16.0300

MD5: 2b520cb9ac3714f35fa4b6d20a3910c1 SHA-1: 05a708c65514d84639b7810088488acdc33b6f97 SHA-256: 66705441f12de8bed48779449b93ac73a4c3d3ccd1127e7d81f13d034c7688f5

60 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1203 Exploitation for Client Execution

The file is an Excel spreadsheet containing Excel 4.0 macros, which are known to be used for malicious purposes. The macros are likely designed to download and execute a secondary payload, a common technique for initial access and further compromise. Due to the obfuscated nature of the extracted macro content, specific IOCs could not be reliably extracted.

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` `717400eb7dc659588a2991d2f6c2375e633541f0f829d9ec99a67e1041db46b7`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet1.bin	97804 bytes

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