2021/10/19 by Caspar Schwarz-Schilling, Joachim Neu, Schwarz-Schilling, Caspar +9 · 3 citations
Computer Science · Social Sciences · #Access Control and Trust #Cryptography and Security (cs.CR) #Distributed systems and fault tolerance #FOS: Computer and information sciences #Internet Traffic Analysis and Secure E-voting
paper · pdf · doi:10.48550/arxiv.2110.10086
openalex publication_date 2021/10/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
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.