CVE-2026-12670 IBM MQ Denial of Service

Medium 5.3 Published 19 Oct 2026 Updated 19 Oct 2026

An authenticated attacker can cause a denial of service in IBM MQ by sending a specially crafted message that triggers excessive memory operations.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-12670?

CVE-2026-12670 is a medium-severity denial of service vulnerability in IBM MQ Advanced container images, published on 19 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

IBM MQ could allow an authenticated attacker to cause a denial of service through a specially crafted message that triggers excessive memory operations during character set conversion.

Weakness: CWE-681

Which versions are affected by CVE-2026-12670?

It affects 2 products.

Products include Ibm Mq Operator, Ibm Supplied Mq Advanced Container Images.

How do I fix CVE-2026-12670?

No fix has been published for CVE-2026-12670 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-12670 being exploited?

There is no known exploitation of CVE-2026-12670 in the wild and no public exploit code.

Sources

Also known as GHSA-mmjj-225r-72h6.