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

Static analysis result for SHA-256 65f3769d9d35a907…

MALICIOUS

Office (OLE) / .DOC

164.0 KB Created: 2020-04-17 13:13:48 Authoring application: Microsoft Excel
MD5: 3ae42729fa595af659a5eb94b6872928 SHA-1: 7119ea018bd53b43096b4d8662acb8e6b4394bf9 SHA-256: 65f3769d9d35a9079815ad2e01c3e7e01188bc71046de340251a255767e5dba6
100 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic

The sample is an encrypted Excel 4.0 macro sheet, indicated by the OLE_XLM_ENCRYPTED_MACROSHEET heuristic. The presence of numerous macro sheets and the 'AUTOOPEN' heuristic suggest that malicious code is intended to execute automatically when the document is opened. The document body is heavily obfuscated and unreadable, preventing further analysis of its specific intent.

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.