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 through 3.5.1, and SC2 versions 3.2.0 through 3.2.10. The vulnerability arises when a client connects to an IBM MQ Queue Manager, specifically targeting the AMQRMPPA channel process. Exploitation of this flaw causes a segmentation fault (SIGSEGV) in the channel process, leading to its termination. The MQ Operator is a Kubernetes operator designed to manage IBM MQ instances, which are widely used enterprise messaging middleware facilitating reliable and secure message queuing and integration between applications. The vulnerability does not impact confidentiality or integrity directly but results in a denial of service (DoS) condition by crashing a critical channel process responsible for message transport. The CVSS v3.1 base score is 6.5 (medium severity), reflecting network attack vector (AV:N), low attack complexity (AC:L), requiring privileges (PR:L), no user interaction (UI:N), unchanged scope (S:U), no impact on confidentiality or integrity (C:N/I:N), and high impact on availability (A:H). No known exploits are reported in the wild as of the publication date. The vulnerability requires an attacker with some level of privileges to connect to the MQ Queue Manager, which may limit exploitation to internal or authenticated users. However, given the critical role of the AMQRMPPA channel in message routing, successful exploitation could disrupt enterprise messaging workflows, causing application outages or delays in business processes reliant on MQ messaging. No patches or fixes are currently linked, indicating that mitigation may rely on workarounds or access controls until IBM releases updates.

For European organizations, the impact of CVE-2025-27365 can be significant, especially for enterprises relying heavily on IBM MQ for critical messaging infrastructure in sectors such as finance, manufacturing, telecommunications, and government services. The denial of service caused by the channel process crash can interrupt message flows, leading to application downtime, delayed transactions, and potential cascading failures in integrated systems. This disruption can affect business continuity, regulatory compliance (e.g., GDPR requirements for availability), and customer trust. Since the vulnerability requires some level of privilege to exploit, insider threats or compromised internal accounts pose a realistic risk vector. Additionally, organizations using Kubernetes to orchestrate IBM MQ via the MQ Operator may face operational challenges in detecting and recovering from such crashes, impacting containerized environments and cloud-native deployments. The lack of confidentiality or integrity impact reduces the risk of data breaches but does not diminish the operational risk posed by availability loss. European organizations with stringent uptime requirements and critical messaging workloads should prioritize addressing this vulnerability to avoid service interruptions.

1. Restrict access to the IBM MQ Queue Manager interfaces to trusted and authenticated users only, minimizing exposure to potentially malicious clients. 2. Implement strict network segmentation and firewall rules to limit connectivity to MQ Operator-managed services, especially the AMQRMPPA channel endpoints. 3. Monitor MQ Operator and Queue Manager logs for signs of segmentation faults or unexpected channel process terminations to enable rapid detection and response. 4. Employ Kubernetes pod health checks and automated restarts to mitigate downtime caused by channel crashes, ensuring rapid recovery of MQ Operator components. 5. Until official patches are released by IBM, consider deploying temporary workarounds such as disabling or limiting the use of vulnerable channel features if feasible. 6. Conduct regular privilege audits to ensure only necessary users have access to MQ management functions, reducing the risk of exploitation by insiders or compromised accounts. 7. Stay informed on IBM security advisories and apply patches promptly once available. 8. Test recovery procedures in staging environments to ensure business continuity plans can handle MQ Operator disruptions effectively.