All news with #crystals-kyber tag

Signal Protocol's Path to Quantum-Resistant Messaging

🔒 Signal has moved to integrate post-quantum cryptography into its messaging stack to mitigate future quantum threats. Phase 1 uses PQXDH, a hybrid handshake combining X25519 with the KEM CRYSTALS-Kyber, to block harvest now, decrypt later attacks. Phase 2 adds SPQR, which runs alongside the Double Ratchet to form a hybrid Triple Ratchet, preserving forward secrecy and post-compromise security while handling larger key sizes, asynchrony, and message loss.

Signal Adds SPQR Triple Ratchet to Harden Against Quantum

🔐 Signal announced the rollout of SPQR (Sparse Post‑Quantum Ratchet), a new cryptographic component that augments its existing double ratchet to form a Triple Ratchet. SPQR integrates post‑quantum Key‑Encapsulation Mechanisms (ML‑KEM, including CRYSTALS‑Kyber) with efficient chunking and erasure coding to limit bandwidth. The design was co-developed with PQShield, AIST, and NYU, formally verified, and will be gradually enabled; users only need to keep clients updated.