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

Static analysis result for SHA-256 91df3b511e19946a…

MALICIOUS

Office (OLE) / .DOC

113.3 KB Created: 2009-02-26 07:53:00 Authoring application: Microsoft Office Word
MD5: 95bf87e46693a82f4f550d8f8add77e9 SHA-1: cc92d32790022de468d72374364943cd1cec5fa8 SHA-256: 91df3b511e19946aee1898d22883fffa7c390dd59b9bca9626325b19a9df9f7f
100 Risk Score

Malware Insights

The sample is a malicious OLE document with a large amount of slack space, indicating hidden or obfuscated content. A critical heuristic identified XOR-encoded strings with a key of 0xC2, suggesting an attempt to hide malicious code. No document body content beyond a single word was extracted, and no scripts were found. The obfuscation techniques and lack of clear user-facing content point to a malicious document, likely a downloader or dropper, but the exact payload and delivery mechanism cannot be determined with high confidence.

Heuristics 2

  • XOR-encoded strings (key 0xC2) critical SC_XOR_ENCODED
    Found 2 Windows library/API name(s) XOR-encoded with single-byte key 0xC2: 'advapi32.dll', 'RegOpenKeyExA'
  • OLE document has large unaccounted-for region high OLE_SLACK_ANOMALY
    OLE file is 116,046 bytes but its declared streams total only 16,543 bytes — 99,503 bytes (86%) 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).