Payload URL assembled from a Chr()/Asc() string expression

OLE_VBA_EXPR_DROPPER_URL

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high OLE_VBA_EXPR_DROPPER_URL

What it means

VBA builds its stage-2 download URL char-by-char from string literals + Chr()/Asc()/StrReverse() (no numeric array); URLs recovered.

Why it fires

The macro assembles its stage-2 download URL character by character from string literals concatenated with Chr()/Asc()/StrReverse() results — often nested (Chr(Asc(Chr(Asc("h")))) = "h") and split across the + and & operators, sometimes emitted via Print #n, into a second-stage VBScript/PowerShell file. There is no numeric array to brute-force and the URL is never contiguous on disk, so the literal scan and the array recoverers all miss it (the "adobeacd-update" maldoc family). A bounded VBA value-expression evaluator resolves the expressions and harvests the URL. Self-validating: only a valid host URL that is not already present verbatim in the macro is reported, so a benign macro cannot false-positive.

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