Sources: National Vulnerability Database, CVE.org, CISA KEV, FIRST EPSS
CVE-2026-13271 Overview
IBM MQ 9.2.0.0 through 9.2.0.44 LTS, 9.3.0.0 through 9.3.0.42 LTS, 9.4.0.0 through 9.4.0.26 LTS, 9.4.0.0 through 9.4.5.1 CD, and 10.0.0.0 through 10.0.0.5 LTS and CD Managed File Transfer could allow an authenticated attacker to obtain sensitive information or cause a denial of service due to improper restriction of XML external entity references in command queue processing.
Critical Impact
Affected Products
- IBM MQ: see the vendor advisory for the exact affected versions
Discovery Timeline
- 2026-11-04: CVE-2026-13271 published to the National Vulnerability Database by psirt@us.ibm.com
- 2026-11-04: last updated in the NVD database
Technical Details for CVE-2026-13271
Vulnerability Analysis
CVE-2026-13271 is a XML External Entity weakness (CWE-611: XML External Entity) in IBM MQ. Based on its CVSS vector, the flaw can be reached over the network, needs some level of access, and needs no user interaction. XML parsing can be abused to read files or reach internal systems.
With a CVSS base score of 8.1, apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Root Cause
The weakness is classified as CWE-611: XML External Entity. XML parsing can be abused to read files or reach internal systems.
Attack Vector
Based on the CVSS vector, the flaw can be reached over the network, needs some level of access, and needs no user interaction. Attack complexity is low complexity.
No exploitation in the wild is confirmed by CISA at the time of the last update. Check the references below for any vendor or researcher proof of concept.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Detection Methods for CVE-2026-13271
Detection Strategies
- Inventory every instance of IBM MQ and compare the running version with the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Run an authenticated vulnerability scan once your scanner ships a check for this CVE.
Monitoring Recommendations
- Forward IBM MQ application, access and audit logs to your SIEM for retrospective hunting.
- Alert on new processes, configuration changes or outbound connections from the affected service.
- Track the vendor advisory and the CISA KEV catalog for changes in exploitation status.
How to Mitigate CVE-2026-13271
Immediate Actions Required
- Apply the fixed version of IBM MQ named in the vendor advisory.
- Prioritize internet facing and business critical instances first.
- Rescan after the change to confirm the exposure is closed.
Workarounds
- If patching must wait, restrict network access to the affected service and place it behind authentication or a web application firewall rule.
CWE References
- CWE-611: XML External Entity More CVEs with this weakness
Technical References
This entry is built directly from NVD, CISA KEV and EPSS data. Verify fixed versions in the vendor advisory before you deploy.
Frequently asked questions
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