In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: nv: Fix null ptr deref on nested wp/unmap, teardown race Commit… (CVE-2026-98467)

The Linux kernel's KVM arm64 nested virtualization implementation had a race condition between kvm_nested_s2_unmap() and kvm_arch_flush_shadow_all() during nested stage 2 page table teardown. Specifically, concurrent execution could cause kvm->arch.mmu.pgt to be set to NULL while another function attempted to dereference it, leading to a NULL pointer dereference. The problem was introduced by commits that added VNCR_EL2 invalidation and nested MMU range teardown. The resolution involved abstracting the invalidation to a new function and adding a NULL check before dereferencing the page table pointer.

This vulnerability could cause a NULL pointer dereference in the kernel, potentially leading to a kernel crash (denial of service) on affected systems running KVM with arm64 nested virtualization. There is no indication of code execution or privilege escalation from the provided data.

A fix has been implemented in the Linux kernel source code to address this issue by adding a NULL pointer check and restructuring the invalidation logic. Users should apply the official Linux kernel updates that include this fix. Since this is not a cloud service, remediation requires updating the affected Linux kernel version once the patch is released. Patch status is not yet confirmed in the provided data; check the vendor advisory or Linux kernel mailing lists for the official patch and update guidance.