CVE-2015-4943 in WebSphere MQ Light
Summary
by MITRE
IBM WebSphere MQ Light 1.x before 1.0.2 allows remote attackers to cause a denial of service (MQXR service crash) via a series of connect and disconnect actions.
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Analysis
by VulDB Data Team • 07/02/2022
IBM WebSphere MQ Light 1.x before 1.0.2 contains a vulnerability that enables remote attackers to trigger a denial of service condition through carefully crafted sequences of connect and disconnect operations. This flaw resides in the MQXR service component which handles client connections and session management within the messaging infrastructure. The vulnerability manifests when multiple rapid connect and disconnect cycles are initiated against the service, causing it to crash and become unavailable to legitimate users. The root cause involves insufficient input validation and state management within the connection handling logic, where the system fails to properly account for connection lifecycle transitions under high-frequency stress conditions. This weakness aligns with CWE-129, Input Validation, and CWE-691, Insufficient Control Flow Management, as the service does not adequately validate connection parameters or maintain proper control flow during concurrent connection operations.
The operational impact of this vulnerability extends beyond simple service disruption as it can be exploited to create sustained denial of service conditions that may require manual intervention to restore service availability. Attackers can leverage this flaw to repeatedly establish and terminate connections, consuming system resources and eventually exhausting the service's capacity to handle legitimate requests. The vulnerability affects the core messaging functionality of WebSphere MQ Light, potentially disrupting critical business processes that depend on message queuing and inter-application communication. Organizations utilizing this messaging platform may experience cascading failures where dependent systems cannot process messages due to the service crash, leading to broader operational disruptions.
Mitigation strategies should focus on implementing immediate patching to upgrade to IBM WebSphere MQ Light 1.0.2 or later versions that contain the necessary fixes for connection handling and resource management. Network-level protections can include rate limiting and connection throttling to prevent rapid succession of connect/disconnect sequences from overwhelming the service. Monitoring solutions should be deployed to detect unusual connection patterns and alert administrators to potential exploitation attempts. The vulnerability demonstrates characteristics consistent with attack patterns found in the MITRE ATT&CK framework under the T1499.004 technique for Network Denial of Service, where adversaries exploit service weaknesses to disrupt availability. Additionally, implementing proper input sanitization and connection state validation would address the underlying control flow management issues that enable this vulnerability to persist. Organizations should also consider implementing connection pooling and session management controls to reduce the impact of malformed connection sequences on overall system stability.