Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 33a422740551e9e9…

MALICIOUS

Office (OLE)

30.5 KB Created: 1999-07-19 14:17:43 First seen: 2012-06-14
MD5: 00abb680b046596124b1df2891363ec8 SHA-1: 3ffebc91368e220ffcfbb28a4e5702539dee2d2c SHA-256: 33a422740551e9e98723d8d22c4936ab6dd3a662092b05d8eb0838421a1ca74d
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic

The sample is identified as a malicious Excel 5 macro-virus, specifically the Laroux family, indicated by critical heuristic firings. The presence of 'laroux' and 'auto_open' markers suggests the macro executes automatically. The embedded OLE structure also shows suspicious findings, further supporting its malicious nature.

Heuristics 3

  • Excel 5 Laroux/Larou-CV macro-virus marker cluster critical OLE_XLS5_LAROUX_MACRO_VIRUS
    Legacy Excel workbook contains a Laroux/Larou-CV macro-virus marker cluster including auto_open execution and workbook/module replication strings. This is a narrow indicator for an infected legacy Excel macro workbook.
  • Embedded Office document has suspicious static findings critical EMBEDDED_OFFICE_CHILD_STATIC_TRIAGE
    A CFB/OLE Office document was found inside another file type and its carved contents matched Office exploit or payload heuristics. This catches wrapped exploit documents where the top-level file routes to a PE, archive, or generic scanner instead of Office.
  • CFB header with no readable streams medium OLE_PARSE_EMPTY_STREAMS
    The file begins with a valid OLE2/CFB header but exposes no directory streams. A non-empty compound document with an unreadable directory is anomalous — it is seen with truncated/corrupt files and, more importantly, with content deliberately shifted off byte boundaries to defeat parsers while the host application still recovers the object.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_office_off0000661e.ole embedded-office Embedded OLE/CFB Office body inside ole container at offset 0x661E 5090 bytes
SHA-256: 0b10584b57b492b6034bba21e32fc869b912fe2d6102cd129d2610e9d182f7e9