CVE-2026-67235

Summary

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 max_message_size. The size check ran only when assembly completed. By declaring body_size = 2^63-1 and then streaming fragments, a client ensured that check_msg_size never fired, so the accumulated body size went unbounded. A reader process accumulates memory until the memory alarm fires, degrading all publishers cluster-wide, or until the node runs out of memory. The memory alarm provides only partial mitigation, since it is reactive rather than preventive. AMQP 0-9-1 is the most widely used protocol, and any publisher can trigger this condition. Preconditions include Any authenticated AMQP 0-9-1 client with publish permission can exploit this.. This issue is fixed in versions 4.3.0, 4.2.6, 4.1.11, 4.0.20, and 3.13.15.

Affected Software

VendorProductVersion RangeStatus
rabbitmqrabbitmq-server>= 4.2.0, < 4.2.6affected
rabbitmqrabbitmq-server>= 4.1.0, < 4.1.11affected
rabbitmqrabbitmq-server>= 4.0.0, < 4.0.20affected
rabbitmqrabbitmq-server>= 3.13.0, < 3.13.15affected

Weaknesses

  • CWE-770: CWE-770: Allocation of Resources Without Limits or Throttling

References