JBIG2 stream contains an implausibly large number of segments

PDF_JBIG2_HUGE_SEGMENT_COUNT

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What it means

JBIG2 stream declares thousands of segments where real-world scanned-document JBIG2 typically contains tens to a few hundred.

Why it fires

Hand-crafted JBIG2 streams designed to stress the segment-graph allocator or refcounter are a recurring exploit primitive. On its own this is a weak signal but it contributes when paired with other JBIG2 anomaly rules.

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