Ml-Dsa

Every conversation about post-quantum risk starts with the same story: adversaries are recording encrypted traffic today and will decrypt it when quantum computers arrive. That threat — Harvest Now, Decrypt Later (HNDL) — is real, and I covered it in detail in Encryption on Borrowed Time. But HNDL has a twin that gets far less attention, and it is the one that should set your migration calendar. Trust Now, Forge Later (TNFL) uses the same mathematics to attack a different target. Instead of breaking the key exchange that protects a recorded session, it breaks the signature that anchors trust. The result is not exposed data — it is forged identity. And unlike HNDL, there is no cleaning it up after the fact. ...

I gave this talk at PA TechCon 2026 in Harrisburg on August 13. The audience was Pennsylvania state and local government IT leaders — CIOs, CISOs, procurement officers, and the county IT directors who keep the lights on with two-person teams. The premise fits in one sentence: Pennsylvania’s data has a shelf life measured in decades, and the encryption protecting it has a shelf life measured in years. Nobody has done the subtraction. ...

Post-quantum cryptography is no longer a standards exercise. ML-KEM key exchange is the default in every major browser and in OpenSSH. RHEL 10 ships with post-quantum TLS and SSH enabled out of the box. DigiCert is issuing ML-DSA certificates today. But “available” and “deployed” are not the same thing. Key exchange is largely solved. Authentication — the part where certificates, signatures, and trust chains live — is not. The gap between what the standards define and what production systems can actually verify is where most of the engineering work remains. ...

In August 2024, NIST published FIPS 204, finalizing ML-DSA (Module-Lattice Digital Signature Algorithm, formerly CRYSTALS-Dilithium) as the first post-quantum digital signature standard. Six months later, RFC 9881 defined how to encode ML-DSA keys and signatures in X.509 certificates. PKI.Next supports all three ML-DSA security levels today. This post explains what that means in practice, how the implementation works, and why the engineering is harder than just swapping an algorithm. The Quantum Threat to PKI Every X.509 certificate ever issued relies on one assumption: that certain mathematical problems are hard enough that an attacker cannot reverse a signature. RSA depends on integer factorization. ECDSA depends on the discrete logarithm problem in elliptic curve groups. Both problems are believed to be computationally infeasible with classical computers. ...