CVE-2026-43347 is a vulnerability in the Linux kernel affecting arm64 platforms using Qualcomm Monaco hardware. The kernel incorrectly accesses hypervisor-owned memory due to incomplete reservation of the Gunyah hypervisor metadata region, causing synchronous external abort exceptions and kernel crashes. The issue arises because the EFI memory map does not fully reserve the hypervisor memory region, leading to allocation of physical frames inside this protected area. The fix involves reserving the full 512 KiB Gunyah metadata region and marking it as no-map to prevent kernel mapping and allocation.