The vulnerability is a CWE‑909 flaw in the KVM hypervisor’s handling of the ID register initialization flag for non‑protected pKVM guests. During VM startup, the hypervisor copies a flag from the host indicating the ID registers are initialized, but it fails to copy the actual register values. As a result, the hypervisor believes the registers are ready while they remain zeroed, causing feature checks to fail. This failure prevents critical system registers such as TCR2_EL1, PIR_EL1, and POR_EL1 from being saved and restored during world switches, which can corrupt the processor state and break VM isolation.

The issue affects the Linux kernel’s KVM implementation on ARM64 platforms. All kernel releases that include the vulnerable code path – currently the 6.14 series and the 7.0 release candidates (rc1‑rc7) – are potentially impacted, as the relevant patches appear in recent kernel git commits.

The CVSS score of 8.8 indicates a high severity flaw. The EPSS score is below 1%, meaning the likelihood of exploitation is very low, and the vulnerability has not been listed in CISA’s KEV catalog. Exploitation likely requires control over a non‑protected VM or the host, and while the exact attack vector is inferred from the description rather than explicitly stated, it is therefore a local or privileged attack scenario. Based on the description, it is inferred that state corruption could lead to privilege escalation or denial of service within the virtualized environment.