Per-transaction encryption to fight malicious MEV

Malicious MEV attacks remain a serious threat on Ethereum: research found almost 2,000 sandwich attacks occur daily and more than $2 million is extracted from the network each month. MEV exploits the mempool’s transparency, where transaction data is visible before execution.

Early threshold-encrypted mempools that used per-epoch keys left some transactions exposed; Flash Freezing Flash Boys (F3B) instead applies threshold encryption per transaction so each transaction stays confidential until finality. F3B has users encrypt the transaction with a symmetric key, then threshold-encrypts that key for a designated Secret Management Committee (SMC).

The ciphertext pair is stored by consensus while the SMC withholds decryption shares until the transaction is committed; once enough shares are released post-finality, the consensus group reconstructs the symmetric key, decrypts the transaction and executes it.

mev, sandwich attacks, mempool, threshold encryption, per transaction, f3b, symmetric key, smc, finality, consensus