Message Header Structure Vulnerability in IBM MQ by IBM
CVE-2026-12538

5.4MEDIUM

Key Information:

Vendor

IBM
Status
MQ Appliance
Vendor
CVE Published:
4 November 2026

What is CVE-2026-12538?

IBM MQ versions 9.4.0.0 to 9.4.0.26, 9.4.1.0 to 9.4.5.3, and 10.0.0.1 to 10.0.0.5 exhibit a vulnerability where authenticated attackers can exploit improper validation of message header structure length fields. This flaw can lead to exposure of sensitive information or potentially result in a denial of service, compromising the overall integrity and security of the messaging system.

Affected Version(s)

MQ Appliance 9.4.0.0 <= 9.4.0.26

MQ Appliance 9.4.1.0 <= 9.4.5.3

MQ Appliance 10.0.0.1 <= 10.0.0.5

References

https://www.ibm.com/support/pages/node/7293035
vendor-advisorypatch

CVSS V3.1

Score:
5.4
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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