关键词: 椭圆曲线, 数字签名, 离散对数, 安全隐患, 攻击方法

Abstract: Elliptic Curve Digital Signature Algorithm(ECDSA) is used more and more widely in many applications. By analyzing an improved algorithm of ECDSA, the paper points out its security risk, analyzes its root causes for insecurity, and puts forward an attack method. Such an attack method has the opportunity to obtain a signer’s private key with little calculated amount and without the computation of discrete logarithm.

Key words: elliptic curve, digital signature, discrete logarithm, security risk, attack method