Office (OLE) / .XLS malware analysis — malicious · f397f061c42ac2a4

MALICIOUS

Office (OLE) / .XLS

469.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel

MD5: 3ac6401e1073063b4a9d6bbba0c674fe SHA-1: 424e4d562331a876d21772fd3757264be0e848e7 SHA-256: f397f061c42ac2a46914680cd373afbd295f0d54b6ed3406d951b516f28a9802

140 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1204.002 Malicious File

The file contains Excel 4.0 (XLM) macros, specifically an Auto_Open defined name, which is a critical indicator of malicious intent. The macro sheet contains a reference to a URL, 'http://star-mineiro.ch/casrtnoar/count.php', which is likely used to download and execute a second-stage payload. The presence of the Auto_Open macro and the external URL strongly suggests a macro-based download and execution attack.

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` `877b24336da75137a3a99cda7752c4a2d3bef2725374cfe3b531d5b368960619`	xlm-macro	oletools.olevba.extract_all_macros (XLM macro listing)	14228 bytes

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