CVE-2026-23402 Linux Kernel KVM x86/mmu逻辑错误漏洞

/* * PoC Concept for CVE-2026-23402 * Triggering SPTE overwrite warning in KVM. * Requires specific kernel config and KVM setup. */ #include <stdio.h> #include <sys/ioctl.h> #include <fcntl.h> #include <linux/kvm.h> int main() { int kvm_fd = open("/dev/kvm", O_RDWR); if (kvm_fd < 0) { perror("open /dev/kvm"); return -1; } // Create VM and VCPU (Simplified) int vm_fd = ioctl(kvm_fd, KVM_CREATE_VM, 0); // ... Setup guest memory and run ... // The vulnerability is triggered by host userspace writes // that conflict with shadow-present SPTEs in direct MMUs. // This usually involves manipulating memory regions via KVM_SET_USER_MEMORY_REGION // while the guest is active to cause a mismatch in pfn checks. printf("Check dmesg for: WARNING: arch/x86/kvm/mmu/mmu.c\n"); close(kvm_fd); return 0; }