The Linux kernel vulnerability CVE-2026-64167 involves the function kho_fill_kimage() unconditionally populating KHO metadata for every kexec image type, including crash kernels. Since crash kernels operate in a limited reserved memory region, the KHO scratch areas can reside outside this region, leading to kernel paging faults during crash kernel initialization (kho_memory_init()). Although kho_locate_mem_hole() already skipped KHO logic for crash kernels, kho_fill_kimage() lacked this check, causing invalid memory references. The fix adds the missing guard in kho_fill_kimage(), ensuring that KHO metadata is not populated for crash kernel images, which resolves the faulting behavior on arm64 and x86 architectures.

If unpatched, crash kernels using kexec could experience kernel paging faults during initialization, potentially causing system instability or failure to properly handle crash recovery scenarios. This affects the reliability of crash kernel execution but does not indicate direct code execution or privilege escalation. No known exploits in the wild have been reported.

A fix has been implemented in the Linux kernel source to add a guard in kho_fill_kimage() that skips KHO metadata population for crash kernel images. Users should apply the official Linux kernel updates that include this fix. Since this is a kernel-level fix, updating to a patched kernel version is the recommended remediation. Patch status is not explicitly stated here; check the Linux kernel vendor advisories or mainline kernel repositories for the specific fixed versions.