CVE-2026-43062 Linux内核蓝牙L2CAP类型混淆漏洞

/* * Conceptual PoC for CVE-2026-43062 * Demonstrating the struct size mismatch and offset error. */ #include <stdio.h> #include <stdint.h> // Correct struct (2 bytes) struct l2cap_ecred_reconf_rsp { uint16_t result; // Offset 0 } __attribute__((packed)); // Incorrect struct used in bug (8 bytes) struct l2cap_ecred_conn_rsp { uint16_t dcid; uint16_t scid; uint16_t result; // Offset 6 uint16_t maxlen; } __attribute__((packed)); int main() { // Simulate a valid 2-byte response packet unsigned char packet[2] = {0x00, 0x00}; // Buggy code cast struct l2cap_ecred_conn_rsp *rsp = (struct l2cap_ecred_conn_rsp *)packet; // 1. Size check fails (requires 8, got 2) if (sizeof(*rsp) != 2) { printf("[VULN] Length check fails: expected %lu, got 2\n", sizeof(*rsp)); } // 2. If length check bypassed (e.g. padding), offset read is wrong unsigned char padded[8] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF}; rsp = (struct l2cap_ecred_conn_rsp *)padded; printf("[VULN] Reading result from offset 0: 0x%04x\n", ((struct l2cap_ecred_reconf_rsp*)padded)->result); printf("[VULN] Buggy code reads result from offset 6: 0x%04x\n", rsp->result); return 0; }