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

Static analysis result for SHA-256 03808d3f8eaafd81…

MALICIOUS

Office (OLE) / .DOC

27.0 KB Created: 1997-03-25 08:52:00 Authoring application: Microsoft Word 6.0
MD5: 26cb72a0526019cba91bd1567682ed3e SHA-1: 42aa58a294f39d570956b11c7e9b66984fbce65b SHA-256: 03808d3f8eaafd816f621a320760c625a8eea5d43af56f05ef5c692bfee9c637
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The file is a malformed OLE document, indicated by significant slack space and anomalous stream parsing. This suggests an attempt to exploit vulnerabilities in older Microsoft Word versions, likely for client execution. No specific malware family could be identified due to the lack of script content or network indicators.

Heuristics 3

  • 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.
  • OLE document has large unaccounted-for region high OLE_SLACK_ANOMALY
    OLE file is 27,648 bytes but its declared streams total only 9,528 bytes — 18,120 bytes (66%) live in unallocated sector slack. This is the canonical hiding place for pre-macro-era Office exploit payloads (XOR-encoded shellcode reached via a parser pointer-corruption bug in the document structure).
  • 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_off00001a40.ole
aa6dbef9fda32fc8a49cce1e49d3ea29b87a8dbf7fac2aa084707f46de73ae02
embedded-office Embedded OLE/CFB Office body inside ole container at offset 0x1A40 20928 bytes