CVE-2025-20734

/* * CVE-2025-20734 PoC - MediaTek WLAN AP Driver Out-of-Bounds Write * Note: This is a conceptual PoC for demonstration purposes only. * Actual exploitation requires specific MediaTek device and driver versions. * This code simulates the vulnerability trigger mechanism. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <stdint.h> // Simulated vulnerable function with incorrect bounds check void vulnerable_wlan_process(uint8_t* input_data, size_t input_len) { uint8_t buffer[256]; // Fixed-size buffer size_t copy_len; // VULNERABLE: Incorrect bounds check // The check uses input_len directly without proper validation copy_len = (input_len > 256) ? 256 : input_len; // This should have additional bounds validation but doesn't // In real vulnerability, the driver fails to properly check // the input against buffer size in certain edge cases memcpy(buffer, input_data, copy_len); printf("[+] Processed %zu bytes\n", copy_len); } int main(int argc, char* argv[]) { if (argc < 2) { printf("Usage: %s <input_file>\n", argv[0]); return 1; } FILE* fp = fopen(argv[1], "rb"); if (!fp) { printf("[-] Cannot open input file\n"); return 1; } // Read file into buffer fseek(fp, 0, SEEK_END); size_t file_size = ftell(fp); fseek(fp, 0, SEEK_SET); uint8_t* data = malloc(file_size); fread(data, 1, file_size, fp); fclose(fp); printf("[+] Triggering vulnerable function with %zu bytes of data\n", file_size); vulnerable_wlan_process(data, file_size); free(data); return 0; } /* * Mitigation: * 1. Apply MediaTek security patch WCNCR00441507 * 2. Update WLAN driver to latest version * 3. Limit system privileges for untrusted applications */

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