SIKE

Supersingular isogeny key encapsulation — the elegant NIST alternate broken in 2022 by a classical attack running on a laptop.

Core Principles & Analysis

• Castryck and Decru's key-recovery attack ran in about an hour on a single core — no quantum computer required.
• SIKE had survived four NIST rounds and offered the smallest keys of any candidate.
• Its fall is the standing argument for backup standards built on independent mathematics.

Specifications & Metrics

• FAMILY: Isogeny-based
• STATUS: Broken
• YEAR: 2022