{"id":"CVE-2026-12538","title":"IBM MQ Appliance is affected by an improper validation vulnerability","summary":"IBM MQ 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 could allow an authenticated attacker to obtain sensitive information or cause a denial of service due to improper validation of message header structure length fie…","severity":"medium","cvss":5.4,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L","cvssSource":"cna","cwe":["CWE-124"],"vendor":"IBM","product":"MQ Appliance","affected":["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"],"published":"2026-11-04","updated":"2026-11-04","sourceUpdated":"2026-11-04T20:25:41.490Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-12538","references":[{"url":"https://www.ibm.com/support/pages/node/7293035"}],"tags":["cve.org"],"ingestedAt":"2026-11-05T21:36:00.556Z","epss":0.00333,"epssPercentile":0.26676,"slug":"CVE-2026-12538","body":"## Overview\n\nIBM MQ 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 could allow an authenticated attacker to obtain sensitive information or cause a denial of service due to improper validation of message header structure length fields.\n\n## Affected\n\n- `mq_appliance >= 9.4.0.0 <= 9.4.0.26`\n- `mq_appliance >= 9.4.1.0 <= 9.4.5.3`\n- `mq_appliance >= 10.0.0.1 <= 10.0.0.5`\n\n## Remediation\n\nThis vulnerability is addressed under APAR DT500605.\n\n\n\nIBM strongly recommends addressing the vulnerability now.\n\n\n\nIBM MQ Appliance version 9.4 LTS\nApply  IBM MQ Appliance fix pack 9.4.0.30 https://www.ibm.com/support/fixcentral/swg/selectFixes , or later firmware.\n\n\n\nIBM MQ Appliance version 9.4 CD - M2003\nUpgrade to  IBM MQ Appliance 10.0.0.6 https://www.ibm.com/support/fixcentral/swg/selectFixes , or later firmware.\n\n\n\nIBM MQ Appliance version 9.4 CD - M2002\nApply  IBM MQ Appliance cumulative security update 9.4.5.4 https://www.ibm.com/support/fixcentral/swg/selectFixes , or later firmware.\n\n\n\nIBM MQ Appliance version 10 LTS\nApply  IBM MQ Appliance cumulative security update 10.0.0.6 https://www.ibm.com/support/fixcentral/swg/selectFixes , or later firmware.","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":29.7,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}