IBM PowerVM Hypervisor: integer overflow

High8.4CVE-2026-17091 · Published Aug 19, 2026 · updated Aug 25, 2026

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.