Catenaa, Thursday, June 04, 2026- A blockchain security researcher helped recover roughly $2 million worth of ether locked inside a failed 2016 Ethereum ICO contract, reviving funds that had remained inaccessible for nearly nine years because of a coding flaw.
The developer, known online as Florent, said the recovery involved approximately 1,003 ETH trapped within the HongCoin token sale contract, one of the many early Ethereum fundraising projects launched during the initial coin offering boom.
Florent said the contract’s refund mechanism contained a vulnerability tied to outdated Solidity code that prevented most investors from reclaiming their ether after the project failed to meet funding targets.
The recovery operation allowed 48 original investors to regain access to previously frozen funds.
According to Florent, the HongCoin contract lacked overflow protection safeguards later introduced through Ethereum’s SafeMath security framework.
Years of partial refunds reduced an internal contract counter to a level that blocked larger token holders from successfully claiming their ETH.
The developer discovered that a little-used administrative minting function could trigger an overflow reset, lowering certain balances to one token and allowing refund conditions to pass.
Because the function required authorization through HongCoin’s multisignature wallet, Florent contacted the original team rather than exploiting the contract independently.
The team reportedly signed 41 separate transactions enabling the recovery process after Florent tested the procedure through a Foundry mainnet simulation environment.
The incident highlights how billions of dollars in older smart contracts may still contain overlooked vulnerabilities or inaccessible funds.
Researchers said many early Ethereum contracts were built before modern smart contract security standards emerged, leaving legacy code vulnerable to flaws involving arithmetic overflows and poorly designed refund logic.
The recovery also comes during renewed scrutiny of decentralized finance security after hundreds of millions of dollars in recent protocol exploits.
At the same time, the case demonstrates how whitehat researchers increasingly play a critical role in protecting blockchain ecosystems and recovering stranded assets.
Florent said the recovery effort was motivated by curiosity and a desire to understand older smart contract architectures rather than profit.
The researcher also noted that artificial intelligence tools remain unreliable for advanced smart contract vulnerability analysis because models often incorrectly assume older contracts are impossible to unlock.
Florent recently built a self-hosted Ethereum scanning system designed to identify contracts holding more than 100 ETH for further security analysis.
Ethereum’s ICO boom between 2016 and 2018 produced thousands of experimental smart contracts, many written before modern auditing standards became common.
Numerous abandoned or failed projects still hold inaccessible crypto assets due to coding mistakes, lost keys or broken refund systems.
Meanwhile, DeFi security remains under pressure following a series of major exploits in 2025 and 2026, including large-scale cross-chain and liquidity protocol attacks.
