On April 9, a single Miner Extractable Value (MEV)-boost relay block on the Ethereum Beacon Chain rewarded Lido, an Ethereum liquid staking solution, with 689 Ether worth $1.28 million. This is one of the largest rewards received in recent months, second only to the 691 Ether awarded to Lido on March 20. The block in question, number 17007842, was finalized on April 9 and contained 47 transactions, and was built by beaverbuild.org according to transaction data.
— MEV-Boost Bot (@mevproposerbot) April 9, 2023
This significant reward has drawn attention to the use of MEVBlocker, a service that prevents Ethereum transactions from being exploited by bots extracting value through MEV exploits. According to MEVBlocker, MEV bots have extracted more than $1.38 billion from Ethereum users attempting to trade, provide liquidity, and mint nonfungible tokens (NFTs).
— Martin Köppelmann 🇺🇦 (@koeppelmann) April 9, 2023
MEV-boost relays are able to extract value by aggregating blocks from multiple builders to select the one with the highest fees. One common type of MEV exploit is the “sandwich” attack, where an attacker places a large trade on either side of a target’s transaction, manipulating the price and profiting from the price change.
MEV-boost relays stem from the concept of Proposer-Builder Separation (PBS), introduced by the Ethereum research organization Flashbots in 2021. Separating the role of proposers from block builders promotes more competition at the consensus level, decentralizes the Ethereum network, and strengthens censorship resistance. However, Ethereum has encountered several censorship issues since The Merge took place, namely compliance with standards laid down by the Office of Foreign Assets Control (OFAC), although the number of compliant blocks has since fallen.
Currently, there are 10 active relays, with Flashbots responsible for relaying more than 50% of the MEV-boost blocks since MEV was introduced in 2021, according to MEVBoost.org. As Ethereum continues its transition to proof-of-stake in September, it will be important to consider and address potential vulnerabilities and exploits such as MEV.