CVE-2025-27365 is a use-after-free vulnerability (CWE-416) affecting multiple versions of the IBM MQ Operator, including LTS 2.0.0 through 2.0.29, CD versions 3.0.0, 3.0.1, 3.1.0 through 3.1.3, 3.3.0, 3.4.0, 3.4.1, 3.5.0, 3.5.1, and SC2 versions 3.2.0 through 3.2.10. The vulnerability arises when a client connects to an MQ Queue Manager and triggers a SIGSEGV (segmentation fault) in the AMQRMPPA channel process, causing it to terminate unexpectedly. This termination results from improper handling of memory, specifically a use-after-free condition, where the software accesses memory after it has been freed, leading to instability and crashes. The vulnerability requires network access (AV:N), low attack complexity (AC:L), and low privileges (PR:L) but does not require user interaction (UI:N). The scope is unchanged (S:U), and the impact is limited to availability (A:H) with no confidentiality or integrity impact. The CVSS v3.1 base score is 6.5, categorizing it as a medium severity issue. No known exploits are currently reported in the wild, and no official patches have been linked yet. The vulnerability affects the stability and availability of IBM MQ Operator deployments, which are critical components in enterprise messaging and integration architectures, potentially causing denial of service (DoS) conditions when exploited.

For European organizations, the impact of CVE-2025-27365 primarily concerns availability disruptions in messaging infrastructure. IBM MQ Operator is widely used in enterprise environments to manage IBM MQ Queue Managers on Kubernetes clusters, facilitating reliable message queuing and integration between applications. A successful exploitation can cause the AMQRMPPA channel process to crash, leading to service interruptions and potential cascading failures in dependent systems. This can disrupt business-critical workflows, especially in sectors relying heavily on real-time messaging such as finance, manufacturing, telecommunications, and public services. Although confidentiality and integrity are not directly impacted, the availability loss can result in operational downtime, financial losses, and reputational damage. The requirement for low privileges means that insider threats or compromised internal accounts could exploit this vulnerability more easily. Given the critical role of IBM MQ in transaction processing and inter-application communication, prolonged outages could affect compliance with service-level agreements and regulatory mandates prevalent in Europe, such as GDPR and sector-specific regulations.

To mitigate CVE-2025-27365, European organizations should take the following specific actions beyond generic patching advice: 1) Monitor and restrict network access to MQ Operator endpoints, especially the AMQRMPPA channel, using network segmentation and firewall rules to limit exposure to trusted clients only. 2) Implement strict role-based access control (RBAC) within Kubernetes to minimize the number of users and services with privileges sufficient to trigger the vulnerability (PR:L). 3) Deploy runtime monitoring and anomaly detection tools that can identify abnormal MQ Operator process crashes or SIGSEGV signals, enabling rapid incident response. 4) Use Kubernetes pod disruption budgets and automated restart policies to ensure quick recovery of MQ Operator pods after crashes, minimizing downtime. 5) Conduct regular configuration audits to ensure MQ Operator versions are tracked and updated promptly once patches become available. 6) Engage with IBM support and subscribe to security advisories to receive timely updates and recommended fixes. 7) Consider temporary compensating controls such as deploying redundant MQ Operator instances or failover mechanisms to maintain message queue availability during remediation. These targeted mitigations help reduce the attack surface, detect exploitation attempts early, and maintain service continuity.