Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 462b9c3c22cc64c3…

MALICIOUS

Office (OLE)

35.5 KB Created: 2020-11-25 10:44:11 Authoring application: Microsoft Excel
MD5: 501af3b2dae97eb94cdd731516882e71 SHA-1: ca10c611e72c9539c56ac3754d29deef269375c8 SHA-256: 462b9c3c22cc64c3b38d090695b566ada4635ceee426548415b101a0bc74b7c7
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The critical heuristics indicate the presence of Excel 4.0 macros with an Auto_Open entry, which is a common method for executing malicious code upon opening an Excel file. The macro sheet contains a reference to a dangerous formula API (RUN=0), suggesting it is designed to execute commands or download additional payloads. The document body contains obfuscated text, further supporting the malicious intent.

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.

FilenameKindSourceSize
xlm_macros.txt
a06afc9fa09c79866169b1def66f92d3e34e9d9517da1c3d48748ca04ec84d45
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6540 bytes