GMX Hacked for $40M, Hacker Returns Funds for $5M Bounty After On-Chain Appeal Cybercriminals GMX Hacked for $40M, Hacker Returns Funds for $5M Bounty After On-Chain Appeal Do Son July 14, 2025 0 GMX was hacked for $40M via smart contract exploit. The hacker returned funds for a $5M bounty after GMX's on-chain appeal, sparking debate in the security community.