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 causing a virtual processor to become permanently unresponsive, requiring a full platform re-IPL to restore normal operation. In some cases this may also cause the guest to inject a small amount of data into hypervisor or partition memory with no attacker control over the target location. Successful exploitation results in an integrity and availability impact to the managed system.