OLE document has large unaccounted-for region

Well-formed Office binary documents pack data into named streams with little slack. When the file is dramatically larger than its declared streams (>40% slack and >16 KB of unaccounted bytes), the extra bytes live in unallocated sectors. Pre-macro-era Word/Excel exploits (e.g. CVE-2010-3333, CVE-2014-1761, CVE-2015-2424) commonly hide XOR-encoded shellcode in this region, reached via a parser pointer-corruption bug in the document structure. The finding is a structural triage signal, not malicious evidence on its own, and carries no verdict score.