Unreferenced OOXML part contains shellcode

OOXML_ORPHAN_PART_SHELLCODE

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critical OOXML_ORPHAN_PART_SHELLCODE

What it means

A package part not referenced by any relationship carries executable shellcode.

Why it fires

An OOXML package part that no relationship references contains a shellcode prolog or API-hash resolver (e.g. a Metasploit stub hidden as xl/media/*.bin). Legitimate packages never ship an orphan binary part containing shellcode, so this is a smuggled payload read by another component at runtime.

Other Office heuristics

OLE_VBA_AFFINE_MSI_DOWNLOADER OLE_VBA_AUTOEXEC_FRAGMENTED_SHELL OLE_VBA_DESTRUCTIVE_WORKBOOK_SHUTDOWN OLE_VBA_BIDIRECTIONAL_MACROCOPY_REPLICATION OOXML_BRAND_LINK_MISMATCH_LURE CVE_2016_7262 POLYGLOT_OOXML_REL_COMMAND OLE_RAW_PCODE_CROSS_DOCUMENT_REPLICATION OLE_VBA_CROSS_WORKBOOK_REPLICATION OOXML_XLM_DANGEROUS_FN OFFICE_DEFAULT_PASSWORD_VBA_DROP_EXEC OFFICE_EMBEDDED_SWF EMBEDDED_OFFICE_CHILD_STATIC_TRIAGE OFFICE_EMBEDDED_MACRO_OBJECT OLE_EMBEDDED_EXE OLE_VBA_EMBEDDED_PE_DROPPER OLE_ENCRYPTED_AND_MALFORMED CVE_2017_11882_EQUATION_NATIVE_CMD_RELATED CVE_2017_11882 OLE_EQUATION_OLE10NATIVE_DOWNLOADER OLE_MTEF_NATIVE_CODE_STUB OLE_EQUATION_OLE10NATIVE_SHELLCODE OOXML_XLM_MACRO_IN_WORKSHEET OLE_XLS5_LAROUX_MACRO_VIRUS