Office (OLE) malware analysis — malicious · f1f89edcdf4f4556

MALICIOUS

Office (OLE)

35.5 KB Created: 2020-11-25 10:44:26 Authoring application: Microsoft Excel

MD5: 11f99b697bb830bf20b770d88acf606a SHA-1: 7409f574a6a46b7cfb9444a55a518aa609a3f1c7 SHA-256: f1f89edcdf4f4556d15993a6fd3bae2062133671df1ddd2414ad5c8cfbaba33c

140 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1203 Exploitation for Client Execution

The file is an Excel 4.0 macro-enabled workbook detected with critical heuristics indicating the presence of an Auto_Open macro. This macro is configured to use dangerous formula APIs, specifically identified as 'RUN=0', suggesting it is designed to execute arbitrary code. The macro sheet contains numerous obfuscated strings and references to potentially dangerous functions, strongly indicating its purpose is to download and execute a second-stage payload.

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` `2341e0ed515ce6c26ba0e339a5195f1cff2203d6a8a183bf8388d5916a1847b6`	xlm-macro	oletools.olevba.extract_all_macros (XLM macro listing)	6423 bytes

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