CVE-2026-11729 in IBM
Summary
by MITRE • 09/15/2026
IBM MQ 9.1.0.0 through 9.1.0.37 LTS, 9.2.0.0 through 9.2.0.43 LTS, 9.3.0.0 through 9.3.0.41 LTS, 9.3.0.0 through 9.3.5.1 CD, 9.4.0.0 through 9.4.0.25 LTS, 9.4.0.0 through 9.4.5.1 CD, and 10.0.0.0 could allow an authenticated attacker to execute arbitrary code in client applications due to unsafe deserialization that enables JNDI injection attacks.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability identified affects multiple versions of IBM MQ including the Long Term Support releases from version 9.1.0.0 through 9.1.0.37, 9.2.0.0 through 9.2.0.43, and 9.3.0.0 through 9.3.0.41, as well as the Continuous Delivery releases from version 9.3.0.0 through 9.3.5.1, 9.4.0.0 through 9.4.0.25 and 9.4.0.0 through 9.4.5.1, along with version 10.0.0.0. This flaw represents a critical security risk within the message queuing infrastructure provided by IBM MQ, which is widely deployed in enterprise environments for reliable asynchronous communication between distributed applications. The core issue stems from unsafe deserialization practices inherent in how certain client-side components process incoming data streams. When an authenticated attacker interacts with these vulnerable versions of the software, they can exploit this weakness to execute arbitrary code on systems running affected client applications.
The technical mechanism behind this vulnerability involves improper validation and sanitization of serialized objects during the deserialization process. Deserialization is a common operation in Java-based enterprise middleware where binary data representing an object is converted back into its original form for use by the application. However, if the system trusts input from untrusted sources without sufficient verification, it becomes susceptible to injection attacks. In this specific case, the unsafe handling of serialized payloads allows attackers to manipulate the deserialization logic to perform Java Naming and Directory Interface injections. This technique leverages the ability to reference external classes or resources during object reconstruction, effectively bypassing standard security controls that might otherwise prevent direct code execution.
The operational impact of this vulnerability is severe due to its potential for remote code execution under authenticated conditions. While authentication is required to initiate an attack, many enterprise environments rely on internal network segmentation and trusted user bases, which can create a false sense of security. Once the attacker successfully injects malicious JNDI references, they gain the ability to execute arbitrary commands with the privileges of the compromised client application process. This could lead to complete system compromise, data exfiltration, lateral movement within the network, or disruption of critical business processes that depend on IBM MQ for message delivery and transaction integrity. The attack vector is particularly dangerous because it targets the client side rather than just the server, expanding the potential blast radius beyond centralized infrastructure components to individual endpoints.
From a classification perspective, this vulnerability aligns with CWE-502 Deserialization of Untrusted Data, which highlights the risks associated with processing data from unverified sources without adequate integrity checks or type validation. Furthermore, it maps directly to MITRE ATT&CK technique T1190 Exploit Public-Facing Application and specifically leverages JNDI Injection patterns often seen in high-profile enterprise software exploits such as Log4Shell variants. The use of JNDI injection indicates that the attacker can potentially load remote class definitions or access directory services, which may facilitate further reconnaissance or privilege escalation depending on the surrounding infrastructure configuration.
Mitigation strategies must focus primarily on applying vendor-provided patches to update IBM MQ installations to versions where this deserialization flaw has been remediated. Organizations should prioritize updating all affected client applications and server components running within their environment. In addition to patching, implementing strict network segmentation can help limit exposure by ensuring that only authorized systems can communicate with IBM MQ endpoints. Security teams should also enforce principle of least privilege for service accounts associated with message queue operations to minimize the impact if a compromise occurs. Monitoring logs for unusual deserialization activity or unexpected outbound connections from client applications may provide early detection indicators, although proactive patching remains the most effective defense against this specific class of vulnerability.