[Introduction]: Cross-chain DeFi platform Poly Network was hacked on August 10, 2021, with the alleged hacker draining up to $610 million in crypto. But just a few days later, the hacker promised to return the stolen assets. Hacking is not uncommon in the crypto world, but this is the first time that a heist involving such a large amount of funds has been reported. Soon, the Poly Network hack was placed among the largest in the crypto industry. What is the whole story of this shocking incident? Why is the Poly Network a target for hacker attacks? What can we learn from it? How do users relieve the security risk in crypto trading and investment? This article will inspire you on security in DeFi. [Key words]: Poly Network, Cross-chain protocol, “White Hat” hacker, DeFi, Re-Entrancy attacks Click here to read:[Hot Spots]: Poly Network Heist — Alarm Bells in DeFi Security Gate.io Blog As a new information section of Gate.io, the Gate.io blog function will provide users with all-round investment support. It will offer the most timely information in the industry, as well as informative columns, exclusive research reports, interesting encyclopedia info, and other high-quality content. All of these combined will enable you to grasp the most valuable and high-quality information without leaving home. We invite you to experience and bookmark this blog, in order to get essential investors tips. Website: https://www.gate.io/en/blog/bloglist App will be launched soon, please keep an eye out for it! Blog entry: “About-Gate Blog” at the bottom of Gate.io homepage. Gate.io Blog will be updated at regular intervals. Stay tuned! Gate.io is a Cryptocurrency Trading Platform Since 2013 Top ranking, Trustworthy, Transparent Sign up to enter the crypto gateway and get 40% commission from referrals Download iOS/Android App right now. Follow us on social media Twitter: https://twitter.com/gate_io Telegram：https://t.me/gateio Instagram：https://www.instagram.com/gateioglobal Medium：https://medium.com/@gateio Gate.io Team August 25, 2021