IBM PowerVM Hypervisor firmware versions FW1120.00, FW1110.00 through FW1110.30, FW1060.00 through FW1060.80, and FW950.00 through FW950.H2 are affected by an out-of-bounds write vulnerability (CWE-787) in partition firmware during network boot. An attacker on the same network segment as a partition undergoing network boot can send a malformed network packet to trigger arbitrary code execution in the partition firmware. This attack compromises the partition's confidentiality, integrity, and availability, but does not affect other partitions or the managed system. The vulnerability requires network proximity and targets only partitions actively performing network boot.

Successful exploitation allows an unauthenticated attacker on the same network to execute arbitrary code in the firmware of a partition during its network boot process. This leads to full compromise of the affected partition's confidentiality, integrity, and availability. Other partitions and the overall managed system are not impacted by this vulnerability.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, limit network access to partitions during network boot to trusted sources only and monitor network boot processes for anomalous packets. Avoid performing network boots in untrusted network environments.