PDF paints image(s) but contains no text operators

Phishing PDFs are often built by exporting a screenshot to PDF: a single page with one or more image XObjects and no text. The carrier evades text-based scanners (no keywords to match) and delivers its call-to-action purely through rendered pixels — a phone number to call, a QR code to scan, or a link the user is told to type. Distinct from PDF_IMAGE_LURE, which requires a small file and an in-PDF click-action; the detector has neither constraint and looks inside compressed content streams to avoid false positives on real text-bearing PDFs.