Miners may alter the timestamp associated with a mined block to avoid increasing network difficulty.
According to a study article released by The Hebrew University in Israel, the “first proof of a consensus-level assault on a major cryptocurrency” has been identified.
On-chain data seems to verify the assertion since one of the paper’s authors, Aviv Yaish, pointed out that F2Pool’s block timestamps were adjusted intentionally to increase payouts. In the publication, the consensus-level attack is known as an Uncle Maker attack due to the “uncle” blocks utilised in the hack.
The blocks of the Ethereum blockchain represent a series of records that are examined, disseminated, and confirmed throughout the network. Uncle blocks are legal blocks removed from the main chain but continue to earn rewards.
“The technique enables an attacker to replace rivals’ main-chain blocks with its own block after the fact, leading the miner of the substituted block to lose all transaction fees for the transactions included in the block, which is demoted from the main-chain.”
Miners may set a block’s timestamp within “a certain acceptable limit within a few seconds.” The report also emphasised that F2Pool’s “creator has made a rather well-publicized denunciation of competitor mining pools, accusing them of assaulting his mining pool,” while “F2Pool are targeting other mining pools.”
The official financial effect of the hack has not yet been determined; however, Yaish informed: “For every successful instance of the assault, F2Pool collected 14 percent more in block rewards and all of the transaction fees included inside. We strive to provide solid estimates for both of your inquiries based on real-world facts, which will be published as soon as they become available!”