CVE-2026-33662 OP-TEE整数下溢致拒绝服务漏洞

/* * PoC Concept for CVE-2026-33662 * This demonstrates the logic error leading to integer underflow. */ #include <stdio.h> #include <string.h> #include <stdint.h> // Simulating the vulnerable function logic void vulnerable_encode(size_t modulus_size, size_t digest_size) { printf("Modulus size: %zu, Digest size: %zu\n", modulus_size, digest_size); // The vulnerable calculation: (modulus_size - 3 - digest_size - 8) // If modulus_size is small enough, this underflows size_t ps_size = modulus_size - 11 - digest_size; printf("Calculated PS size: %zu\n", ps_size); if (ps_size > 1024) { printf("[!] Integer underflow detected! PS size is huge.\n"); printf("[!] Calling memset with this size will cause a crash/DoS.\n"); // In the real vulnerability, this memset crashes the TEE // memset(buffer, 0xFF, ps_size); } else { printf("[-] PS size is normal.\n"); } } int main() { // Normal scenario printf("--- Normal Case ---\n"); vulnerable_encode(2048, 32); // Exploit scenario: Using a very small modulus // This causes (64 - 11 - 32) to underflow if types are not handled, // or simply demonstrates the boundary condition. // In the actual bug, the subtraction results in a massive number. printf("\n--- Exploit Case (Small Modulus) ---\n"); // Assuming a context where modulus size is smaller than required overhead + digest vulnerable_encode(40, 32); return 0; }