Saint Raccoon, Who Rummaged in the TLS Timings

Patron of TLS handshakes, the Diffie-Hellman exchange, and everyone who reuses the same ephemeral key out of laziness.

Life

On 9 September 2020 a group of researchers revealed Raccoon, a timing attack against the Diffie-Hellman exchange in TLS. When a server reused the same ephemeral key and with measurable timing, a patient attacker could reconstruct the shared secret and decrypt the connection. It took a lot of luck and a lot of measurements, but the raccoon knows how to rummage a long time before it finds something.

Prayer

O Saint Raccoon, who rummages among the microseconds of the handshake, let our servers never reuse the same ephemeral key. Amen.

How to celebrate

Celebrated by disabling DH key reuse and preferring exchange over elliptic curves.

Reuse the ephemeral key and you leave crumbs for the raccoon.