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

Static analysis result for SHA-256 1f764e796ddafde5…

MALICIOUS

Office (OLE) / .XLS

101.0 KB Created: 2021-12-15 12:06:31 Authoring application: Microsoft Excel
MD5: 82a2ec411430a35993a1edcfaa31482e SHA-1: a4ee393a27915fb14ac234af79cbb2596a66a24a SHA-256: 1f764e796ddafde59fbb16c337ea805da870f3c44add863826505e378cafd3cf
60 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications

The sample is an encrypted Excel 4.0 macro sheet, indicated by the OLE_XLM_ENCRYPTED_MACROSHEET heuristic. The presence of an OLE_XLM_AUTOOPEN heuristic suggests that the macro sheet is designed to execute automatically upon opening the file. No specific IOCs were extracted, and the document body was unreadable.

Heuristics 2

  • 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.
  • 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.