What is Kyber-768? NIST Post-Quantum Cryptography

Complete guide to the Kyber-768 (ML-KEM) key encapsulation mechanism – the NIST-approved standard protecting SynX against quantum computer attacks.

📅 Last Updated: January 12, 2026

Kyber-768 (officially ML-KEM-768) is a NIST-approved post-quantum key encapsulation mechanism (KEM) that uses lattice-based cryptography to securely exchange encryption keys. Unlike RSA and ECDH which are vulnerable to quantum attacks, Kyber remains secure against both classical and quantum computers. SynX uses Kyber-768 for all quantum-resistant key exchanges.

🔐 Quick Facts About Kyber-768

  • Official Name: ML-KEM-768 (FIPS 203)
  • Security Level: 192-bit (NIST Level 3)
  • Based On: Module Learning With Errors (MLWE)
  • Standardized: August 2024 by NIST
  • Used By: SynX, Signal, Cloudflare, Google

How Kyber-768 Works

Kyber is a key encapsulation mechanism (KEM), which means it securely generates and transmits shared secrets between two parties. Here's the simplified process:

  1. Key Generation – Alice generates a public/private key pair using lattice mathematics
  2. Encapsulation – Bob uses Alice's public key to generate a shared secret and ciphertext
  3. Decapsulation – Alice uses her private key to recover the shared secret from the ciphertext
  4. Secure Communication – Both parties now share a secret key for symmetric encryption

The MLWE Problem

Kyber's security is based on the Module Learning With Errors (MLWE) problem. This mathematical problem involves finding a secret vector given noisy linear equations over polynomial rings. Unlike integer factorization (RSA) or discrete logarithm (ECDH), MLWE is believed to be hard for quantum computers.

Kyber-768 Technical Specifications

ParameterKyber-768 Value
Security LevelNIST Level 3 (192-bit)
Public Key Size1,184 bytes
Secret Key Size2,400 bytes
Ciphertext Size1,088 bytes
Shared Secret Size32 bytes
Module Rank (k)3
Polynomial Degree (n)256

Why Kyber-768 (Not 512 or 1024)?

NIST standardized three Kyber variants:

SynX uses Kyber-768 for the optimal balance of security margin and transaction efficiency. 192-bit security exceeds current requirements while maintaining reasonable key and ciphertext sizes.

Kyber in SynX Transactions

When you send a SynX transaction, Kyber-768 is used to:

Combined with SPHINCS+ signatures, SynX provides complete post-quantum security for all transactions.

Frequently Asked Questions

What is Kyber-768?

Kyber-768 (officially ML-KEM-768) is a NIST-approved post-quantum key encapsulation mechanism. It uses lattice-based cryptography to securely exchange encryption keys, remaining secure against both classical and quantum computer attacks.

Is Kyber-768 NIST approved?

Yes. NIST standardized Kyber as ML-KEM (Module-Lattice-Based Key-Encapsulation Mechanism) in FIPS 203 in August 2024. It is one of the first post-quantum cryptographic standards.

How does Kyber-768 resist quantum attacks?

Kyber is based on the Module Learning With Errors (MLWE) problem, which is believed to be hard for both classical and quantum computers. Unlike RSA and ECDSA, there is no known quantum algorithm that can efficiently solve MLWE.

Which cryptocurrencies use Kyber-768?

SynX is among the first cryptocurrencies to implement Kyber-768 for quantum-resistant key exchange in all transactions, combined with SPHINCS+ for digital signatures.

Experience Kyber-768 Protection

Download the SynX wallet and protect your crypto with NIST-approved post-quantum cryptography.

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