@techreport{preussmattsson-tls-mlkem1024-x448-01, number = {draft-preussmattsson-tls-mlkem1024-x448-01}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-preussmattsson-tls-mlkem1024-x448/01/}, author = {John Preuß Mattsson and Sini Ruohomaa}, title = {{Post-Quantum Hybrid ML-KEM-1024/X448 Key Agreement for TLS 1.3}}, pagetotal = 9, year = 2026, month = oct, day = 9, abstract = {This document defines a post-quantum/traditional hybrid key exchange algorithm for TLS 1.3 that combines ML-KEM-1024 with X448: MLKEM1024X448. The algorithm provides a hybrid key exchange option targeting a higher security level than X25519MLKEM768, matching the security level of AES-256 and ChaCha20. A large security margin can protect against future cryptanalytic advances, misuse, and implementation errors. Compared with P-curves offering a similar security level, X448 is significantly faster and provides greater implementation robustness. A FIPS-validated implementation of MLKEM1024X448 ensures that the ML-KEM-1024 component is FIPS- validated. The algorithm defined in this document is intended for use with TLS 1.3, DTLS 1.3, and QUIC and follows the general hybrid key exchange construction defined for TLS 1.3.}, }