Description

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 a remote authenticated attacker to execute arbitrary code on the system due to the deserialization of untrusted data.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.8",
  "pubDate": "2026-09-14T21:17:02.130Z",
  "pubdate": "2026-09-14T21:17:02.130Z",
  "executiveSummary": "This vulnerability involves insecure deserialization of untrusted data within various IBM MQ versions, potentially allowing a remote authenticated attacker to achieve arbitrary code execution on the target system.\nAffected products include 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.\nThe vulnerability stems from the improper handling of serialized objects during the deserialization process. By providing a specially crafted payload, an attacker can manipulate the state of the application, leading to the execution of unauthorized instructions with the privileges of the IBM MQ service.\nThe risk implication is critical, as successful exploitation facilitates full system compromise, data exfiltration, or lateral movement within the infrastructure. Exploitation requires the attacker to be authenticated to the IBM MQ environment, necessitating network access to the target service. Organizations are advised to prioritize security patching and implement strict access control measures to mitigate exposure.",
  "technicalDetails": "The vulnerability resides in the way IBM MQ deserializes objects transmitted over the network. Insecure deserialization occurs when the application fails to adequately validate or sanitize the data before reconstructing it into an object instance. When the application logic processes a malicious serialized stream, it can trigger unintended code paths or instantiate unauthorized classes.\nThe root cause is the reliance on insecure deserialization primitives. An attacker, having established an authenticated session with the IBM MQ service, can craft a malicious object payload. This payload is designed to exploit gadgets—existing classes or code segments present within the application's classpath—to influence the execution flow upon deserialization.\nThe attack flow begins with the attacker identifying an entry point where serialized data is accepted by the IBM MQ infrastructure. The attacker injects a binary blob containing a 'gadget chain.' When the IBM MQ service attempts to deserialize this data, the runtime environment invokes specific methods defined by the manipulated object structure.\nThrough the successful chaining of these gadgets, the attacker can force the application to execute arbitrary system commands, effectively bypassing existing security controls. The execution occurs with the same permission set as the IBM MQ broker process. Because IBM MQ often runs with elevated service privileges, the post-exploitation impact includes full control over the underlying host, persistence mechanisms, and access to all managed messaging queues and configuration files.\nThis vulnerability is restricted to authenticated users, meaning the attacker must first possess valid credentials to interface with the messaging system. However, in environments where multiple users have messaging access, this represents a significant privilege escalation and system integrity threat. The exposure is primarily network-based, targeting the interface where the MQ protocol accepts incoming object streams. Because this is a logic-based flaw in object handling, traditional signature-based network intrusion detection systems may struggle to identify the malicious payloads without deep packet inspection of the serialized binary structures."
}