PDF_OPENACTION_HIDDEN_OBJECT — /OpenAction targets an object not reachable from /Root

high PDF_OPENACTION_HIDDEN_OBJECT

What it means

PDF defines an /OpenAction whose target object cannot be reached by walking indirect references from the document /Root catalog tree.

Why it fires

When a PDF is opened, the /OpenAction fires regardless of whether the target object is reachable from the catalog. Many static analysers and indexers enumerate the document via the /Root tree and never see hidden objects — yet the action still runs. This shape is associated with evasive samples that hide JavaScript or launch actions outside the normal catalog descent.

Other PDF heuristics

PDF_LAUNCH_JS_PROTOCOL PDF_LAUNCH_COMMAND PDF_LAUNCH_MSHTA PDF_ADOBE_QR_UNLOCK_LURE PDF_JS_URL_KEYED_READER_EXPLOIT_KIT CVE_2009_2990_U3D_AUTOACTIVATE PDF_ANNOT_AUTHOR_EVAL_STAGER PDF_ANNOT_SUBJECT_HEX_EVAL_STAGER PDF_ANNOT_SUBJECT_MARKER_EVAL_STAGER PDF_JS_BASE_N_TOKEN_DOWNLOADER PDF_BASE64_PE_PAYLOAD PDF_BRAND_INVOICE_LURE_OFFDOMAIN PDF_BRAND_INVOICE_CLOUD_EMAIL_LURE PDF_CORPORATE_PRESENTATION_CLOUD_REDIRECT_LURE PDF_CORRUPTED_FILE_UPDATE_LURE PDF_CRACKED_SOFTWARE_SHORTLINK_LURE PDF_GAME_HACK_SEO_LINK_FARM PDF_DISTRIBUTED_PIRACY_LINK_FARM PDF_DOCUSIGN_DOWNLOAD_LURE PDF_DOCUMENT_ACTION_HOST_MISMATCH_LURE PDF_DYNAMIC_DNS_DOCUMENT_LINK_FARM PDF_SWF_NATIVE_MEMORY_CORRUPTION_PAYLOAD PDF_EMBEDDED_PE_PAYLOAD CVE_2010_1240_EMBEDDED_EXPORT_LAUNCH