Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 c489964b45cd0eb9…

MALICIOUS

Office (OLE)

21.0 KB Created: 1996-02-01 19:05:00 Authoring application: Microsoft Word 6.0 First seen: 2012-10-03
MD5: d75a0b740d03d821c45b3781393bf776 SHA-1: bc1a077162b98e62fa35ff88e341af0525e42bde SHA-256: c489964b45cd0eb961cc03db2e1f91f308ea12ce8c32a547156abc4d4be236fe
140 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.005 Visual Basic

The document contains a legacy WordBasic auto-exec macro marker (AutoOpen), indicating malicious intent. The document body masquerades as a free antivirus installation utility, instructing the user to click a macro button to install the software, which is a common social engineering tactic. The embedded OLE object exhibits anomalies, suggesting deliberate obfuscation or corruption to evade detection.

Heuristics 4

  • 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 19,328 bytes but its declared streams total only 0 bytes — 19,328 bytes (100%) 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).
  • Legacy WordBasic auto-exec macro marker medium OLE_LEGACY_WORDBASIC_AUTOEXEC
    OLE Word document contains a legacy WordBasic auto-execution marker such as AutoOpen, but no modern VBA project was recovered and no stronger macro-virus family marker was present. This is analyst-facing evidence for old Word macro execution surface, not a downloader or parser-CVE attribution by itself.
  • 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_off00000880.ole embedded-office Embedded OLE/CFB Office body inside ole container at offset 0x880 19328 bytes
SHA-256: 7b65dcf380f54a72a6ec43554015224ee9955e2d2d535e6dc60f6cbe393cac02