Zapscape KVM vulnerability allows nested VM escape
🔒 Zapscape (CVE-2026-64561) is a Linux KVM/x86 shadow-MMU flaw that can let an attacker with kernel privileges in an L1 guest escape KVM isolation and run code on the host. Disclosed by researcher Hyunwoo Kim, the issue is a stale-root ordering bug causing a use-after-free during page-fault handling when nested virtualization is exposed. The upstream fix has been merged; administrators should update kernels or vendor packages that backport the patch.
