  This paper presents the first comprehensive analysis of an emerging
cryptocurrency scam named "arbitrage bot" disseminated on online social
networks. The scam revolves around Decentralized Exchanges (DEX) arbitrage and
aims to lure victims into executing a so-called "bot contract" to steal funds
from them.
  To collect the scam at a large scale, we developed a fully automated scam
detection system named CryptoScamHunter, which continuously collects YouTube
videos and automatically detects scams. Meanwhile, CryptoScamHunter can
download the source code of the bot contract from the provided links and
extract the associated scam cryptocurrency address. Through deploying
CryptoScamHunter from Jun. 2022 to Jun. 2023, we have detected 10,442 arbitrage
bot scam videos published from thousands of YouTube accounts. Our analysis
reveals that different strategies have been utilized in spreading the scam,
including crafting popular accounts, registering spam accounts, and using
obfuscation tricks to hide the real scam address in the bot contracts.
Moreover, from the scam videos we have collected over 800 malicious bot
contracts with source code and extracted 354 scam addresses. By further
expanding the scam addresses with a similar contract matching technique, we
have obtained a total of 1,697 scam addresses. Through tracing the transactions
of all scam addresses on the Ethereum mainnet and Binance Smart Chain, we
reveal that over 25,000 victims have fallen prey to this scam, resulting in a
financial loss of up to 15 million USD.
  Overall, our work sheds light on the dissemination tactics and censorship
evasion strategies adopted in the arbitrage bot scam, as well as on the scale
and impact of such a scam on online social networks and blockchain platforms,
emphasizing the urgent need for effective detection and prevention mechanisms
against such fraudulent activity.
