CVE-2026-34667 CAI Content Credentials整数下溢漏洞

#include <stdio.h> #include <stdlib.h> #include <stdint.h> // Simulated vulnerable function in CAI Content Credentials void process_credential_size(uint32_t input_size) { printf("[+] Processing input size: %u\n", input_size); // Vulnerability: Integer Underflow // If input_size is 0, (0 - 1) wraps around to UINT_MAX (4294967295) uint32_t buffer_size = input_size - 1; printf("[+] Calculated buffer size after subtraction: %u\n", buffer_size); // Attempt to allocate memory based on wrapped value // This will likely fail (malloc returns NULL) or cause system instability char *buffer = (char *)malloc(buffer_size); if (buffer == NULL) { printf("[-] Memory allocation failed. Application may crash or hang.\n"); return; } // If allocation succeeds (unlikely for huge size), filling it causes DoS printf("[+] Memory allocated. Writing data...\n"); memset(buffer, 0x41, buffer_size); free(buffer); } int main() { // PoC: Triggering the underflow with 0 printf("--- CVE-2026-34667 PoC Demo ---\n"); process_credential_size(0); return 0; }