Office (OLE) / .XLSX malware analysis — malicious · 7c1c3bdaebc33bd7

MALICIOUS

Office (OLE) / .XLSX

36.0 KB Created: 2020-11-25 10:39:55 Authoring application: Microsoft Excel

MD5: 44cb848425b4718a6ca1c72aecd5c4fe SHA-1: eed490a84581ee7035bea465093ef137f9a60493 SHA-256: 7c1c3bdaebc33bd71a8d6a663117e9cb678a10e06e7ef89e445843a3ad6fd94e

140 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1059.001 PowerShell

The sample contains Excel 4.0 macros, specifically an Auto_Open defined name, which is a critical indicator of malicious intent. The presence of the Auto_Open function suggests that the macro will execute automatically upon opening the spreadsheet. The heuristic 'XLM Auto_Open with dangerous formula APIs' further confirms the use of potentially harmful functions like RUN. This indicates the file is designed to execute arbitrary commands when opened.

Heuristics 3

Excel 4.0 Auto_Open defined name critical OLE_XLM_AUTOOPEN_DEFINEDNAME

oletools recovered an Auto_Open / Auto_Close entry from an Excel 4.0 macro sheet. The raw BIFF name can be tokenized or partially opaque to byte-string checks, but the recovered macro listing confirms the workbook has an XLM auto-execution entry.
XLM Auto_Open with dangerous formula APIs critical OLE_XLM_DANGEROUS_FN

Excel 4.0 macro sheet contains an Auto_Open / Auto_Close entry and dangerous XLM formula APIs that can invoke programs, write files, or transfer control without VBA.
Excel 4.0 (XLM) macro sheet present medium OLE_XLM_AUTOOPEN

Workbook contains an Excel 4.0 macro sheet sub-stream — XLM is rarely seen in modern legitimate workbooks and was a major Office malware vector during 2020-2022.

Extracted artifacts 1

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`xlm_macros.txt` `aded6ecf5bf6272dccb66bccb87d34a5a909412ffa0b97a2e47e8a4aa0519b7b`	xlm-macro	oletools.olevba.extract_all_macros (XLM macro listing)	6570 bytes

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