CVE-2026-10751 in IBM
Summary
by MITRE • 09/18/2026
IBM MQ Java and JMS client libraries could allow an authenticated attacker to execute arbitrary code on client applications due to a deserialization filter bypass in exception handling.
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Analysis
by VulDB Data Team • 09/18/2026
The vulnerability identified within IBM MQ Java and JMS client libraries represents a critical security flaw rooted in the improper implementation of serialization filters during exception processing sequences. In modern enterprise messaging systems, data integrity is paramount, particularly when objects are transmitted between distributed components using formats like Java Object Serialization or JSON-based payloads that may contain serialized state. The specific technical failure occurs within the exception handling mechanisms of these client libraries, where an attacker who has already established authentication with the message broker can manipulate error responses to bypass intended deserialization safeguards. This bypass allows for the injection of maliciously crafted objects that are subsequently processed by the vulnerable application logic without adequate validation or filtering against known dangerous classes.
From a technical perspective, this flaw aligns closely with CWE-502, which describes Deserialization of Untrusted Data. The core issue lies in the fact that while standard message processing paths may employ strict allow-listing or deny-listing strategies to prevent arbitrary code execution via deserialized objects, the exception handling path fails to apply these same rigorous checks. When an error condition is triggered during normal operation, the system generates a response object containing details about the failure. If this response includes serialized data and the library processes it without re-evaluating the security filters applied to primary message streams, an attacker can exploit this inconsistency. By crafting specific payloads that trigger these exception paths, the attacker forces the client application to deserialize untrusted input, leading directly to Remote Code Execution (RCE).
The operational impact of this vulnerability is severe for organizations relying on IBM MQ for mission-critical communication between applications. An authenticated attacker who exploits this flaw can achieve complete control over the affected client system. This level of access enables the exfiltration of sensitive data stored within the application's memory or file system, modification of business logic by altering persistent state, and potentially using the compromised host as a pivot point for further lateral movement within the internal network. Because authentication is required to exploit this vulnerability, it typically affects environments where attackers have already breached perimeter defenses or obtained valid credentials through phishing, credential stuffing, or other initial access techniques. However, in many enterprise architectures, once an attacker gains any foothold with low-level privileges, escalating to code execution on client nodes significantly expands the blast radius of the compromise.
This vulnerability maps directly to several tactics within the MITRE ATT&CK framework, specifically T1059 Command and Scripting Interpreter for executing arbitrary commands after gaining access, and more critically T1203 Exploitation for Client Execution if the attack targets end-user machines running client applications. It also reflects patterns associated with Defense Evasion techniques where attackers exploit inconsistencies in security controls to bypass detection mechanisms like application whitelisting or input validation filters. The existence of such a flaw underscores the importance of consistent security policy enforcement across all code paths, including error handling and logging routines which are often overlooked during development and testing phases.
Mitigation strategies must focus on immediate patching as well as architectural hardening. IBM has released updates that address this deserialization filter bypass in exception handling; organizations should prioritize applying these patches to all affected versions of the Java and JMS client libraries immediately. In addition to software updates, administrators should enforce strict network segmentation to limit which systems can communicate with MQ brokers, thereby reducing the attack surface for authenticated attackers. Implementing robust input validation at application boundaries is also essential, ensuring that any data processed by deserialization mechanisms originates from trusted sources only. Furthermore, deploying runtime application self-protection (RASP) solutions or advanced endpoint detection and response tools can help detect anomalous behavior associated with exploitation attempts, such as unexpected process creation following message receipt, providing an additional layer of defense in depth against this class of vulnerabilities.