x25519mlkem768

X25519MLKEM768 is a post-quantum hybrid key exchange that combines the classical X25519 elliptic curve with ML-KEM-768 (formerly known as Kyber-768). This hybrid approach provides quantum-resistant security while maintaining backward compatibility with classical cryptography. The combination ensures security even if either algorithm is broken: if quantum computers break X25519, ML-KEM-768 provides protection; if ML-KEM-768 has weaknesses, X25519 maintains security. ML-KEM (Module-Lattice-based Key Encapsulation Mechanism) was standardized by NIST in 2024 as part of the post-quantum cryptography initiative. Chrome and other browsers have begun experimental support for hybrid PQ key exchange. This is considered the most practical transition path to quantum-resistant TLS.