Developer Recovers 1,003 ETH Worth $2M Locked in 2016 HongCoin ICO Contract for Nine Years

Security researcher Florent helped recover approximately 1,003 ETH, worth roughly $2 million at current prices, that had been trapped in a 2016 HongCoin ICO contract for nine years, according to The Block. The initial coin offering was meant to auto-refund investors' ETH when it fell short of its goal, but a bug prevented the refund function from processing most claims. Florent identified an integer overflow vulnerability in the contract's outdated Solidity code and used the team's admin function to reset blocked holders' balances, enabling refunds.

Florent coordinated the recovery with HongCoin's multisig wallet, validating the exploit sequence and having the team sign unlock transactions for 41 of 48 original investors. Two investors have already claimed a combined 96.5 ETH and voluntarily sent Florent a whitehat reward, though he emphasized the recovery involved no fees or commissions.