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

Static analysis result for SHA-256 258a98f91e15112f…

MALICIOUS

Office (OLE) / .DOC

81.0 KB Created: 2020-04-23 12:26:24 Authoring application: Microsoft Excel
MD5: b5a14b8177809b3978f59aeb3f7e936f SHA-1: 4bb4f20d472fb216aabf29474ef15643f54b5f4e SHA-256: 258a98f91e15112fe7cff1e3c4bee9082a657fa66eb68e474a96c670046a464b
100 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059.001 PowerShell

The file is an encrypted Excel 4.0 macro sheet, indicated by multiple high-severity heuristic firings. The presence of an 'AUTOOPEN' macro suggests it is designed to execute automatically upon opening. The document body is unreadable, but the heuristics strongly point to a malicious macro-based execution. Without readable script content or further network indicators, the exact payload and family remain unknown.

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.