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Playlist "Squeezing a key through a carry bit"

Squeezing a key through a carry bit

Filippo Valsorda

The Go implementation of the P-256 elliptic curve had a small bug due to a misplaced carry bit affecting less than 0.00000003% of field subtraction operations. We show how to build a full practical key recovery attack on top of it, capable of targeting JSON Web Encryption.