Description
The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. Prior to 5.33.0, the AMQP connection tuning path records the negotiated AMQP frame_max value, but src/main/java/com/rabbitmq/client/impl/SocketFrameHandler.java and NettyFrameHandlerFactory continue to validate broker-controlled frame payload lengths against maxInboundMessageBodySize because the negotiated limit is not applied consistently through setMaxInboundFramePayloadSize. A malicious or compromised broker can send a method frame larger than the negotiated frame_max during or after connection establishment, causing the client to allocate and decode a protocol-invalid frame instead of rejecting it with MalformedFrameException. The protocol violation can disrupt the affected connection and cause client-side denial of service. This issue is fixed in version 5.33.0.
References6
- github.com/rabbitmq/rabbitmq-java-client/commit/08790f09686173e…
- github.com/rabbitmq/rabbitmq-java-client/commit/b491075f42e8996…
- github.com/rabbitmq/rabbitmq-java-client/pull/1994
- github.com/rabbitmq/rabbitmq-java-client/pull/1995
- github.com/rabbitmq/rabbitmq-java-client/releases/tag/v5.33.0
- github.com/rabbitmq/rabbitmq-java-client/security/advisories/GH…
Metrics
- EPSS — exploit probability
- 0% percentile: 42 · as of 11 November 2026
- CWE
- CWE-20
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