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Vol. 1 · Ed. 2026
CyberGlossary
Entry № 768

ML-KEM (FIPS 203)

ML-KEM (FIPS 203) とは何ですか?

ML-KEM (FIPS 203)NIST's standardized post-quantum key encapsulation mechanism, based on the CRYSTALS-Kyber design and published as FIPS 203 in August 2024 — now the default PQ KEM for TLS, IPsec, and hybrid key exchange.


ML-KEM (Module-Lattice-Based Key-Encapsulation Mechanism), standardized as FIPS 203 on 13 August 2024, is the first post-quantum KEM officially standardized by NIST. It is derived from CRYSTALS-Kyber, the winning lattice-based KEM from the NIST PQC competition. The standard defines three parameter sets — ML-KEM-512, ML-KEM-768, and ML-KEM-1024 — targeting AES-128, AES-192, and AES-256-equivalent classical security with quantum resistance under reasonable lattice assumptions. ML-KEM produces encapsulated shared secrets suitable for use with HKDF, allowing it to slot into existing protocols. Hybrid key exchange — combining ML-KEM with classical X25519 via concatenated shared secrets fed into HKDF — was deployed by Apple iMessage (PQ3), Signal (PQXDH), Cloudflare and Google for TLS, and AWS KMS through 2023–2025. Pure ML-KEM (no classical hybrid) is also acceptable per FIPS 203 but most deployments hybridize until lattice cryptography has more years of broad scrutiny. Naming pitfall: the FIPS document uses ML-KEM, but most existing code still says Kyber; treat them as the same family with slight encoding differences between the draft Kyber-768 and final ML-KEM-768.

  1. 01

    TLS 1.3 deployments add the `X25519MLKEM768` hybrid group, sending both classical X25519 and ML-KEM-768 shares in the ClientHello.

  2. 02

    Signal's PQXDH protocol mixes ML-KEM-768 output into the existing X3DH key agreement to provide post-quantum forward secrecy.

よくある質問

ML-KEM (FIPS 203) とは何ですか?

NIST's standardized post-quantum key encapsulation mechanism, based on the CRYSTALS-Kyber design and published as FIPS 203 in August 2024 — now the default PQ KEM for TLS, IPsec, and hybrid key exchange. サイバーセキュリティの 暗号 カテゴリに属します。

ML-KEM (FIPS 203) とはどういう意味ですか?

NIST's standardized post-quantum key encapsulation mechanism, based on the CRYSTALS-Kyber design and published as FIPS 203 in August 2024 — now the default PQ KEM for TLS, IPsec, and hybrid key exchange.

ML-KEM (FIPS 203) はどのように機能しますか?

ML-KEM (Module-Lattice-Based Key-Encapsulation Mechanism), standardized as FIPS 203 on 13 August 2024, is the first post-quantum KEM officially standardized by NIST. It is derived from CRYSTALS-Kyber, the winning lattice-based KEM from the NIST PQC competition. The standard defines three parameter sets — ML-KEM-512, ML-KEM-768, and ML-KEM-1024 — targeting AES-128, AES-192, and AES-256-equivalent classical security with quantum resistance under reasonable lattice assumptions. ML-KEM produces encapsulated shared secrets suitable for use with HKDF, allowing it to slot into existing protocols. Hybrid key exchange — combining ML-KEM with classical X25519 via concatenated shared secrets fed into HKDF — was deployed by Apple iMessage (PQ3), Signal (PQXDH), Cloudflare and Google for TLS, and AWS KMS through 2023–2025. Pure ML-KEM (no classical hybrid) is also acceptable per FIPS 203 but most deployments hybridize until lattice cryptography has more years of broad scrutiny. Naming pitfall: the FIPS document uses ML-KEM, but most existing code still says Kyber; treat them as the same family with slight encoding differences between the draft Kyber-768 and final ML-KEM-768.

ML-KEM (FIPS 203) からどのように防御しますか?

ML-KEM (FIPS 203) に対する防御は通常、上記の定義で述べたとおり、技術的統制と運用上の実践を組み合わせます。

ML-KEM (FIPS 203) の別名は何ですか?

一般的な別名: FIPS 203, Kyber (standardized), Module-Lattice KEM。

関連用語

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