The Ethereum blockchain forked into two competing chains after a bug in the Geth client appeared. About 54% of Ethereum nodes worked with the wrong chain.
The bug affected version of Geth client v1.10.7 and earlier. According to Ethernodes, almost 75% of all Ethereum nodes were using them, so 73% of Geth nodes using outdated software risked separation from the network. This means that 54% of Ethereum nodes were vulnerable.
Despite the fact that the developers reported a bug last week and the Hades Gamma patch became available on Tuesday, today’s “split” of the blockchain indicates that many users have not yet updated their wallets. The Go Ethereum client development team reported that this issue has been fixed in v1.10.8 and urged the node operators to upgrade to the current version as soon as possible.
“There was a consensus bug on the Ethereum mainnet today, which was fixed in Geth v1.10.8. Fortunately, many miners have already been updated and the correct chain is longer, ”- Martin Swende, head of the Ethereum Foundation’s security department, tweeted.
The danger is that the emergence of such a fork could lead to double spend attacks, in which cryptocurrency is spent and then the transaction is overwritten in a longer blockchain. Block Research researchers found that block reorganization began to occur after an attacker exploited this error, which could affect other EVM-compatible chains as well. For example, Binance Smart Chain and Polygon are at risk.
Ethereum core developer Tim Beiko wrote that three mining pools, Flexpool, BTC.com and Binance, were using the old version of Geth. Flexpool was aware of this issue and reported it himself, so the developers tried to contact two other pools. Beiko later clarified that BTC.com had already updated the software.
Last year, Ethereum developers were forced to suspend work on the Berlin hard fork to reduce the network’s dependence on the Geth client. Given its popularity, any defect in this client can lead to the creation of a “false” chain. The planned Berlin hard fork took place in April this year, and the London update was activated in August.
