In this case, RabbitMQ doesn't trust user input - the maximum frame size is negotiated as part of the AMQP protocol. The affected code did have a check that the

In this case, RabbitMQ doesn't trust user input - the maximum frame size is negotiated as part of the AMQP protocol. The affected code did have a check that the frame wasn't bigger than the agreed limit, but there was a chance to overflow before it got there.