Sign Change Fault Attacks on Elliptic Curve Cryptosystems

We present a new type of fault attacks on elliptic curve scalar multiplications: Sign Change Attacks. These attacks exploit different number representations as they are often employed in modern cryptographic applications. Previously, fault attacks on elliptic curves aimed to force a device to output points which are on a cryptographically weak curve. Such attacks can easily be defended against. Our attack produces points which do not leave the curve and are not easily detected. The paper also presents a revised scalar multiplication algorithm that provably protects against Sign Change Attacks.

• Type: Conference
• Year: 2006
• Where: FDTC
• Authors: Johannes Blömer, Martin Otto 0002, Jean-Pierre Seifert
• Keywords: Cryptology, Elliptic Curves, Fault Attacks, FDTC 2006, Sign Change Attacks