# CVE-2026-11716: IBM MQ for HPE NonStop heap buffer overflow in cluster migration

Source: https://junglewise.ai/threats/cve-2026-11716-ibm-mq-for-hpe-nonstop-8-1-0-through-8-1-0-40-could-allow-an  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-18. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-11716 · Severity: high · CVSS 7.5 · Published 2026-09-18

IBM MQ for HPE NonStop is a message queuing middleware used to handle critical enterprise messaging. An authenticated attacker can trigger a heap buffer overflow during queue manager startup by sending malformed cluster migration data, causing service outages or potentially executing arbitrary code on the server.

Technologies: [IBM MQ for HPE NonStop](https://junglewise.ai/threats/technologies/mq-for-hpe-nonstop). Vendors: [IBM](https://junglewise.ai/threats/vendors/ibm).

## Quick answers

**Is CVE-2026-11716 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-11716 being exploited in the wild.

**How severe is CVE-2026-11716?** High severity, with a CVSS score of 7.5, published 18 September 2026.

**Which products and versions are affected?** IBM MQ for HPE NonStop 8.1.0 through 8.1.0.40.

**Is there a fix for CVE-2026-11716?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-11716 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-11716?** Check whether you run IBM MQ for HPE NonStop at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a heap-based buffer overflow (CWE-122) in improper validation of cluster migration data during queue manager startup. An authenticated attacker with network access can exploit this via the MQ cluster protocol to cause denial of service or arbitrary code execution. A fix is available in CSU 8.1.0.41.

## Affected products

- IBM MQ for HPE NonStop 8.1.0 through 8.1.0.40

## Timeline

- 2026-09-18: disclosed

## References

- [https://www.ibm.com/support/pages/node/7287705](https://www.ibm.com/support/pages/node/7287705)

## Related threats

- [IBM MQ for HPE NonStop C client heap overflow in AMS policy handling](https://junglewise.ai/threats/cve-2026-11727-ibm-mq-for-hpe-nonstop-8-1-0-through-8-1-0-40-ibm-mq-c-client)
- [IBM MQ for HPE NonStop out-of-bounds read in message header](https://junglewise.ai/threats/cve-2026-11726-ibm-mq-for-hpe-nonstop-8-1-0-through-8-1-0-40-could-allow-an)
- [IBM MQ heap-based buffer overflow in distribution lists](https://junglewise.ai/threats/cve-2026-11381-ibm-mq-could-allow-an-authenticated-attacker-to-cause-a-denial-of)
- [IBM MQ for HPE NonStop heap buffer underflow in message processing](https://junglewise.ai/threats/cve-2026-10858-ibm-mq-for-hpe-nonstop-8-1-0-through-8-1-0-40-could-allow-an)
- [IBM MQ for HPE NonStop integer overflow in MQINQ validation](https://junglewise.ai/threats/cve-2026-10744-ibm-mq-for-hpe-nonstop-integer-overflow-in-mqinq-validation)