MEV Bots
Hack or exploit on Apr 3, 2023 · Sandwich Attack
What happened
On April 3, MEV bots suffered a malicious sandwich attack that cost them around $25 million. Data on the chain shows that the malicious verifier who attacked the MEV bots today has been punished by Slash and kicked out of the verifier queue. According to SlowMist analysis, the reason why the MEV bots was attacked was that even if the beacon block was incorrect, the relay still returned the payload to the proposer, which resulted in the proposer being able to access the content of the block before another block was finalized. The attacker takes advantage of this problem to maliciously construct an invalid block, so that the block cannot be verified, and the relay cannot broadcast (the status code is 202) to obtain the transaction content in advance. mev-boost-relay has urgently released a new version to alleviate this problem, and it is recommended that relay operators upgrade the relay in time.
Details
- Date
- Apr 3, 2023
- Kind
- Hack or exploit
- Method
- Sandwich Attack
- How in
- Bridge and cross-chain
- Target
- not stated
- Chains
- Ethereum
Reported by
Related incidents
MEV Bot 2023 · Hack or exploit · $1.4M
Ethereum Foundation 2023 · Hack or exploit · $9K
SwanBluechip, "MEV Bots hack, Apr 3, 2023: $25M lost", Crypto hack history, https://swan-hack-tracker.pages.dev/history/i/ht58daca252e/ (data as of 2026-10-31).