NIST Finalizes Post-Quantum Standards as 'Harvest Now, Decrypt Later' Threat Looms

Post-quantum cryptography refers to algorithms built to withstand attacks from both classical and quantum computers, addressing a vulnerability in today's widely used encryption methods. Although no quantum computer can currently break modern encryption, adversaries can collect and store encrypted data now to decrypt it once quantum capability matures — a strategy known as 'harvest now, decrypt later'. In 2024, the US standards body NIST finalized its first post-quantum algorithms, ML-KEM for key exchange and ML-DSA for digital signatures, which governments and large organizations are beginning to adopt. Security experts currently recommend a hybrid approach — pairing classical algorithms with post-quantum ones — so that protection holds unless both simultaneously fail. Organizations are advised to audit their cryptographic usage, prioritize long-lived sensitive data, and rely on vetted libraries rather than custom-built solutions.