CVE-2019-4656

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-03-16 · updated 2026-06-17

Description

IBM MQ and IBM MQ Appliance 7.1, 7.5, 8.0, 9.0 LTS, 9.1 LTS, and 9.1 CD is vulnerable to a denial of service attack that would allow an authenticated user to crash the queue and require a restart due to an error processing error messages. IBM X-Force ID: 170967.

Affected products

IBM MQ: from 8.0.0.0 before 8.0.0.14; from 9.0.0.0 through 9.0.0.9; from 9.1.0 before 9.1.4; from 9.1.0.0 before 9.1.0.4 — fixed in 8.0.0.14, 9.1.0.4, 9.1.4
IBM MQ Appliance: from 8.0.0.0 before 8.0.0.14 — fixed in 8.0.0.14
IBM Corporation WebSphere MQ: from 7.1.0.0 through 7.5.0.9

How to fix

Upgrade to a fixed version: IBM MQ 8.0.0.14, 9.1.0.4, 9.1.4; IBM MQ Appliance 8.0.0.14. Check the vendor advisory for mitigations.

References

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