A double-spend attack is one of the major security issues in most blockchain systems, but it is difficult to successfully launch unless an adversary has massive computing power. In this paper, we introduce a new attack model that combines a double-spend attack with a Sybil attack in the Bitcoin network. We present analysis results that a double-spending attacker can make a block propagation delay by conducting Sybil attacks and increase the probability of winning the mining race, thus successfully launching the double-spend attack. We develop the probability of success of this new attack in mathematics forms and analyze this attack model from the perspective of economics. We present the attacker's break-even point in various situations and demonstrate the effect of the proposed attack.

中文翻译：

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在比特币去中心化网络中通过Sybil攻击进行双重支出

双花攻击是大多数区块链系统中的主要安全问题之一，但是除非对手具有强大的计算能力，否则很难成功发起攻击。在本文中，我们介绍了一种新的攻击模型，该模型在比特币网络中结合了双花攻击和Sybil攻击。我们给出的分析结果表明，双花攻击者可以通过进行Sybil攻击来阻止区块传播，并增加赢得采矿比赛的可能性，从而成功地发起了双花攻击。我们以数学形式开发成功这种新攻击的可能性，并从经济学的角度分析这种攻击模型。我们介绍了攻击者在各种情况下的收支平衡点，并证明了所提议的攻击的效果。