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

Static analysis result for SHA-256 91c05e799c079448…

MALICIOUS

Office (OLE) / .DOC

122.5 KB Created: 2020-04-03 15:27:38 Authoring application: Microsoft Excel
MD5: 51afe266b0d9ac8e9947928591c0494e SHA-1: 585c98a1c45fed780b3dffc2437f1f8f5150c564 SHA-256: 91c05e799c079448d87b45dcb83472ba1009513290157e39fa62fcae06436157
100 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic

The file is an encrypted Excel 4.0 macro sheet, as indicated by multiple heuristic firings including OLE_XLM_ENCRYPTED_MACROSHEET and OLE_XLM_AUTOOPEN. The presence of encrypted macros strongly suggests the document is designed to execute malicious code upon opening. No document body or script content was available for further analysis, limiting the ability to determine the specific payload or delivery mechanism.

Heuristics 3

  • Encrypted Excel 4.0 macro sheet high OLE_XLM_ENCRYPTED_MACROSHEET
    Workbook contains an Excel 4.0 macro sheet and BIFF FILEPASS encryption. Password-protected XLM macro sheets, especially the default Excel password path, are a common malware evasion pattern because static formula extraction may fail until the workbook is decrypted.
  • OLE metadata lists many Excel 4.0 macro sheets high OLE_XLM_DOCPROPS_MACROSHEET_INVENTORY
    Workbook contains a BIFF Excel 4.0 macro-sheet marker and its clear OLE DocumentSummaryInformation stream lists many MacroN sheet titles. This is a useful static signal when FILEPASS encryption prevents formula extraction from the workbook stream.
  • 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.