CVE-2026-17091 Power System Integer Overflow

High 8.4 Published 19 Aug 2026 Updated 20 Aug 2026

A root user in a guest partition can trigger an integer overflow to crash the hypervisor or corrupt memory, impacting system availability and integrity.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-17091?

CVE-2026-17091 is a high-severity vulnerability in IBM PowerVM Hypervisor, published on 19 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

IBM PowerVM Hypervisor FW1120.00, FW1110.00 through FW1110.30, FW1060.00 through FW1060.80, and FW950.00 through FW950.H2 is affected by a vulnerability in the PowerVM hypervisor call interface. An attacker with root access to a guest partition can issue a specially crafted hypervisor call to inject an arbitrary amount of data into hypervisor or partition memory, resulting in either a crash causing a full platform re-IPL and terminating all hosted partitions, or corruption of hypervisor or partition memory. The PowerVM hypervisor will restart automatically; however, repeated exploitation could result in a sustained availability impact. Successful exploitation results in an integrity and availability impact to the managed system.

Weakness: CWE-190

Which versions are affected by CVE-2026-17091?

It affects 26 products.

Products include Ibm Power System E1050 \(9043-Mrx\) Firmware, Ibm Power System E1080 \(9080-Hex\) Firmware, Ibm Power System E1150 \(9043-Mru\) Firmware, Ibm Power System E1180 \(9080-Heu\) Firmware, Ibm Power System E950 \(9040-Mr9\) Firmware, Ibm Power System E980 \(9080-M9s\) Firmware and 20 more.

How do I fix CVE-2026-17091?

No fix has been published for CVE-2026-17091 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-17091 being exploited?

There is no known exploitation of CVE-2026-17091 in the wild and no public exploit code.

Sources

Also known as GHSA-48q4-vhg7-552r.