Recently a research paper was published that could put Ethereum miners into trouble. Israel-based Hebrew University published a research paper consisting of discoveries of initial evidence about consensus-level attacks on Ethereum. However, the research paper is yet to receive reviewed. It was said to utilize the on-chain available data and open source codebase of the Ethereum network to reach conclusions.
The research consists of issues at its core around Ethereum miners. It states that miners are able to bring changes in the mined blocks timestamp and this way they can avoid the network’s increasing difficulty. On-chain available data also seems to support the claims made in the paper.
One of the creators of the research paper – Aviv Yaish – noted the timestamps of F2Pool were manually and artificially altered with the intention of improving rewards for themselves. It’s worth noting that the Ethereum network uses a proof-of-work consensus mechanism which is soon to be replaced by proof-of-stakes in September this year.
The consensus-level attack outlined in the reports was referring to an Uncle Maker attack. This was given reference to the use of ‘uncle’ blocks that were used by miners for exploiting the network. Ethereum blockchain’s blocks are sets of records storing data that gets checked, verified, and distributed across the whole network.
Uncle blocks mentioned in the reports are the blocks that were said to be removed out of the mainnet, however, it is still able to receive rewards. The report outlined that the attack was meant to allow an attacker to replace the main-chain blocks of his competitors. This results in replacing the miner of these blocks losing all transaction fees gained after validating transactions stored within the block.
Miners across the network can set a timestamp of the block within a certain limit, which falls with the difference of a few seconds. One of these pools was F2Pool that was figured out within the research. F2Pool did not consist of even a single block having a timestamp that could match with the expected result.
Source: https://www.thecoinrepublic.com/2022/08/07/ethereum-miners-accused-of-a-consensus-level-attack-on-ethereum/