Recently, two attacks were presented against Proof-of-Stake (PoS) Ethereum: one where short-range reorganizations of the underlying consensus chain are used to increase individual validators' profits and delay consensus decisions, and one where adversarial network delay is leveraged to stall consensus decisions indefinitely. We provide refined variants of these attacks, considerably relaxing the requirements on adversarial stake and network timing, and thus rendering the attacks more severe. Combining techniques from both refined attacks, we obtain a third attack which allows an adversary with vanishingly small fraction of stake and no control over network message propagation (assuming instead probabilistic message propagation) to cause even long-range consensus chain reorganizations. Honest-but-rational or ideologically motivated validators could use this attack to increase their profits or stall the protocol, threatening incentive alignment and security of PoS Ethereum. The attack can also lead to destabilization of consensus from congestion in vote processing.
翻译:最近,有两起攻击针对“控股证据”Etheum案:一起是利用基本共识链的短期重组来增加个别验证人的利润并推迟协商一致决定;另一起是利用对抗性网络延迟来无限期拖延协商一致决定。 我们提供了这些攻击的改良变式,大大放松了对敌对利益和网络时间的要求,从而使得袭击更加严重。 合并了两起改良攻击的技巧,我们获得了第三次攻击,使得对手能够消失一小部分股份,对网络信息传播(假设是概率性信息传播)不加控制,从而导致甚至长期的共识链重组。 诚实但有理性或意识形态动机的验证人可以利用这次攻击来增加他们的利润或拖延协议,威胁刺激性调整和POS Eeterum的安全。 这次攻击还可能破坏选票处理过程中的共识。