CVE-2026-67235 RabbitMQ: AMQP 0-9-1 body assembly never validates accumulated size

RabbitMQ is a messaging and streaming broker. Prior to versions 4.3.0, 4.2.6, 4.1.11, 4.0.20, and 3.13.15, The content-header BodySize a uint64 was stored without validation against maxmessagesize. The size check ran only when assembly completed. By declaring bodysize = 2^63-1 and then streaming...