Malicious Office (OLE) / .XLS — malware analysis report

Static analysis result for SHA-256 8dfcffbebeee41a9…

MALICIOUS

Office (OLE) / .XLS

180.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: f104c26bcd972d1e0db7c9975da222c0 SHA-1: ef645a8850c3b551ec8bc9b458ba40212d3922d0 SHA-256: 8dfcffbebeee41a9e7e829d4e3112f54706f32419bdcfeed78400c83429a640d
160 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File

The sample is an Excel 4.0 (XLM) macro-enabled spreadsheet. It contains an Auto_Open macro that uses dangerous formula APIs, specifically the RUN function, to execute external code. The document body contains multiple URLs that are likely used to download the secondary payload. The presence of an 'enable macros' lure further supports the malicious intent.

Heuristics 4

  • 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.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
917baaae0e48794e5eb73ae3d5cf93c43110b97da5df3e45bc2f236b5551c875
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 27158 bytes