A analysis paper printed by The Hebrew College in Israel stories having found the “first proof of a consensus-level assault on a significant cryptocurrency.” The paper is at present awaiting peer assessment however makes use of publicly accessible on-chain knowledge and Ethereum’s open supply codebase to affirm its conclusions.
At its core, the paper highlights a difficulty 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) At any time when 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
Ethereum is maintained via a proof-of-work consensus mechanism, which will probably be moved to proof-of-stake this September. Nevertheless, thus far, the community seems to be vulnerable 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 information which can be 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 opponents’ 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 will probably be demoted from the main-chain.”
Miners can set a block’s timestamp inside “a sure affordable certain,” usually inside a number of seconds. One mining pool that was singled out within the analysis was F2Pool, which “up to now two years, F2Pool didn’t have even a single block with a timestamp” that matched the anticipated end result. 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 every day rewards.
The paper additionally highlighted that F2Pool’s “founder has made a comparatively properly 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.
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The Hebrew College has “concrete fixes for Ethereum’s protocol” and created a patch for consideration. Yaish said in a weblog submit that the data was “responsibly disclosed to the Ethereum Basis” earlier than publication.