CVE-2026-43109 Linux内核影子栈mmap锁错误处理漏洞

/* * PoC for CVE-2026-43109 * This code demonstrates the context of the vulnerability. * It attempts to trigger signal handling while manipulating memory mappings. * Note: Actual exploitation requires specific kernel version and hardware support (Shadow Stack). */ #include <stdio.h> #include <stdlib.h> #include <signal.h> #include <unistd.h> #include <sys/mman.h> void handle_signal(int sig) { // Signal handler logic write(1, "Signal caught\n", 14); } int main() { // Register signal handler signal(SIGUSR1, handle_signal); printf("Starting PoC for CVE-2026-43109...\n"); // In a vulnerable kernel, we would need to ensure // shstk_pop_sigframe is called and mmap_read_lock_killable fails. // This usually involves a race condition or specific memory pressure. // Raise signal to trigger handler raise(SIGUSR1); return 0; }