⛑️FN Hotspot Express丨GMX Hacked for $42 Million, How Should DeFi Security Be Ensured? On the evening of July 9, another large-scale theft occurred on-chain, with @GMX_IO hacked for $42 million. Here’s a summary of the latest developments and reasons so far: Attack Process and Fund Flow Analysis by security firms @peckshield and SlowMist @SlowMist_Team indicates that the attacker exploited a flaw in GMX V1's AUM calculation logic. This flaw caused the contract to immediately update the global average price after opening a short position. The attacker used this to construct a targeted operation path, achieving token price manipulation and arbitrage redemption. The attacker transferred approximately $9.65 million in assets from Arbitrum to Ethereum, then exchanged them for DAI and ETH. Some of the funds flowed into the mixing protocol Tornado Cash. Approximately $32 million in assets remain on the Arbitrum network, involving tokens such as FRAX, wBTC, and DAI. After the incident, GMX reached out on-chain to the hacker's address, requesting the return of 90% of the funds and offering a 10% white hat bounty. However, according to the latest on-chain data, the GMX hacker has already exchanged the assets stolen from the GMX V1 pool for ETH. The stolen assets include WBTC/WETH/UNI/FRAX/LINK/USDC/USDT. Currently, all assets except for FRAX have been sold and exchanged for 11,700 ETH (approximately $32.33 million), which have been dispersed into four wallets for storage. Therefore, the GMX hacker now holds 11,700 ETH (approximately $32.33 million) and 10.495 million FRAX across five wallets, with a total value of approximately $42.8 million. Analysis by Yu Jin suggests that the hacker's actions likely indicate a rejection of GMX's proposal to repay the assets in exchange for a 10% white hat bounty. For more details on the attack, check it out: