The prosperity of the cryptocurrency ecosystem drives the need for digital asset trading platforms. Beyond centralized exchanges (CEXs), decentralized exchanges (DEXs) are introduced to allow users to trade cryptocurrency without transferring the custody of their digital assets to the middlemen, thus eliminating the security and privacy issues of traditional CEX. Uniswap, as the most prominent cryptocurrency DEX, is continuing to attract scammers, with fraudulent cryptocurrencies flooding in the ecosystem. In this paper, we take the first step to detect and characterize scam tokens on Uniswap. We first collect all the transactions related to Uniswap V2 exchange and investigate the landscape of cryptocurrency trading on Uniswap from different perspectives. Then, we propose an accurate approach for flagging scam tokens on Uniswap based on a guilt-by-association heuristic and a machine-learning powered technique. We have identified over 10K scam tokens listed on Uniswap, which suggests that roughly 50% of the tokens listed on Uniswap are scam tokens. All the scam tokens and liquidity pools are created specialized for the "rug pull" scams, and some scam tokens have embedded tricks and backdoors in the smart contracts. We further observe that thousands of collusion addresses help carry out the scams in league with the scam token/pool creators. The scammers have gained a profit of at least \$16 million from 39,762 potential victims. Our observations in this paper suggest the urgency to identify and stop scams in the decentralized finance ecosystem, and our approach can act as a whistleblower that identifies scam tokens at their early stages.
翻译:加密货币生态系统的繁荣催生了对数字资产交易平台的需求。除了中央交换(CEXs)之外,还引入了分散的交换(DEXs),让用户在不将其数字资产的保管权转移给中间人的情况下进行加密货币交易,从而消除传统的加密货币系统的安全和隐私问题。Uniswap,作为最著名的加密货币DEX的繁荣,正在继续吸引骗骗徒,在生态系统中欺诈性的加密货币泛滥。在本文中,我们迈出了第一步,以探测和描述Unswap上的骗局标牌。我们首先收集了与Unswap V2交换有关的所有交易,并从不同角度调查了Unswap数字资产的加密货币交易的格局。然后,我们提出了一个准确的方法,在Unswap上标注骗局的骗局牌牌牌牌牌牌上,我们发现Unswap上列出的10多个骗局标牌子,在Unswap上显示,大约50 %的标牌子是Unswap货币交易所的骗局。我们所有的骗局和骗局的骗局上,我们所有的骗局和骗局的骗局都是我们的骗局。