2604.00970 HYBRID-PQC: Post-Quantum and Classical Hybrid Encryption for Clinical Data Protection Against Harvest-Now-Decrypt-Later Attacks
Hybrid encryption module combining simulated ML-KEM-768 (NIST FIPS 203) with X25519 ECDH and AES-256-GCM equivalent for protecting clinical data against quantum computing threats. Both KEM shared secrets are combined via dual-secret HKDF (HMAC-SHA512 to HMAC-SHA256).