Aptos rolls out Encrypted queue of pending transactions to curb frontrunning, sandwich attacks

What happened

Layer-1 blockchain Aptos has launched an optional new feature that could help shield traders from attacks involving maximal extractable value (MEV), including frontrunning and sandwich attacks. On Monday, Aptos said its Encrypted Mempool feature is now live on its mainnet, allowing users to opt in to keep pending transactions encrypted until their block ordering is finalized.

The optional feature hides transaction details until their order is finalized, preventing bots from exploiting pending trades. Aptos said the feature was built for institutions submitting large transactions to the chain, traders wanting to avoid MEV risk, AI agents (AI that carries out multi-step tasks rather than answering one question) and builders.

“When you send a transaction on any major chain today, anyone watching the network can see the details before it executes, the function you’re calling, the assets and amounts involved, and the contracts you’re interacting with,” Aptos said. “Bots use that visibility to trade against you or copy your strategy.” Sandwich attacks, one form of MEV attack, cost Ethereum traders about $60 million over the 12 months through October 2025, according to Cointelegraph’s analysis of EigenPhi data .