Saint Sweet32, Martyr of the 64-Bit Ciphers

Patron of 3DES and Blowfish ciphers, TLS sessions that last a lifetime, and blocks that are too small.

Life

On 25 October 2016 Karthikeyan Bhargavan and Gaëtan Leurent of INRIA revealed Sweet32: 64-bit block ciphers like 3DES have a space so small that, after about four billion blocks in the same session, collisions start to reveal pieces of plaintext. They showed they could recover a cookie from an HTTPS session kept open long enough. Since then 3DES has been slowly retired from the protocols.

Prayer

O Saint Sweet32, who waits patiently for the collision, let our ciphers have large blocks and short sessions. Amen.

How to celebrate

Celebrated by disabling 3DES and the other 64-bit ciphers and choosing AES, with a sweet on the side.

Small block, certain collision.