At its core, the paper highlights a problem the place miners can change the timestamp associated to a mined block to keep away from elevated problem on the community. On-chain knowledge seems to help the declare as Aviv Yaish, one of many paper’s authors, highlighted F2Pool’s block timestamps being artificially altered to enhance rewards.
(9/12) Each time F2Pool’s block timestamps attain the purpose the place mining problem is meant to lower, they artificially set them to be one second earlier. F2Pool has been executing this assault over the previous two years, and the proof has been hiding in plain sight! … pic.twitter.com/mDEG2UqXZh
— Aviv Yaish (@yaish_aviv) August 5, 2022
Uncle Maker
Ethereum is maintained by a proof-of-work consensus mechanism, which might be moved to proof-of-stake this September. Nonetheless, thus far, the community seems to be inclined to the assault recognized in by The Hebrew College.
The consensus-level assault is known as an Uncle Maker assault throughout the paper in reference to the “uncle” blocks used within the exploit. Blocks throughout the Ethereum blockchain act as a set of data which are checked, distributed, and verified throughout all the community. Uncle blocks are legitimate blocks which have been faraway from the principle chain however nonetheless obtain rewards.
“The assault permits an attacker to interchange rivals’ main-chain blocks after the very fact with a block of its personal, thus inflicting the changed block’s miner to lose all transactions charges for the transactions contained throughout the block, which might be demoted from the main-chain.”
Miners can set a block’s timestamp inside “a sure affordable sure,” usually inside just a few seconds. One mining pool that was singled out within the analysis was F2Pool, which “prior to now two years, F2Pool didn’t have even a single block with a timestamp” that matched the anticipated consequence. F2Pool is likely one of the largest Ethereum swimming pools working with a hashrate of 129 TH/s and producing roughly 1.5K ETH in each day rewards.
The paper additionally highlighted that F2Pool’s “founder has made a comparatively effectively publicized condemnation of competing mining swimming pools, blaming them for attacking his personal mining pool” whereas, in actuality, “F2Pool are attacking different mining swimming pools.”
The financial affect of the assault has not but been formally recognized, however CryptoSlate reached out Yaish who informed us,
“For every profitable occasion of the assault, F2Pool earned 14% extra from block rewards, and as well as earned all of the transaction charges contained inside.
We’re at present trying to offer concrete estimations for each of your questions utilizing real-world knowledge, which might be printed instantly when we have now them!”
The Hebrew College has “concrete fixes for Ethereum’s protocol” and created a patch for consideration. Yaish said in a blog post that the knowledge was “responsibly disclosed to the Ethereum Basis” earlier than publication.
