Show HN: TutaCrypt, post-quantum encryption protocols for securing emails [pdf] (opens in new tab)

Our core development team are trained to work in applied cryptography and we work directly with the University of Wuppertal cryptographers for cryptanalysis and testing.

To secure our customer's emails we do not only rely on the new post-quantum algorithm but we use a post-quantum Key Encapsulation Mechanism (CRYSTALS-Kyber) in combination with an Elliptic-Curve-Diffie-Hellmann key exchange (x25519). We did choose Kyber for pq encryption because it has been chosen by NIST for standardization. However, we are aware that it still might be broken in the future. In this case our implementation allows us to replace it with a different post-quantum Key Encapsulation Mechanism. Our customer's emails will not be leaked in this case because they are still protected by the state-of-the-art Elliptic-Curve-Diffie-Hellmann key exchange.

As all post-quantum crypto is relatively new there is still the risk of it being broken in the future. This is why we combine the new algorithms with classical ones in an hybrid approach so that the encryption stays at least as secure as it is now.

By mixing it up with classical encryption algorithms. The implementations don’t use pure post quantum cryptography, see SSH.

Learn some math.

SIKE was known to be breakable since at least 1997, specific breaking algorithms were developed in 2000, and these were implemented in Magma (a symbolic algebra suite from John Cannon, Sydney Uni, second generation after the original Cayley system of the mid 1980s).

It wasn't a choice that would have been put forward by people in the abstract algebra game - just something put forward as a 'candidate' by security researchers.

Something something Venn diagrams.