MEV Sandwich Attacks: Private Routing Is No Guarantee
MEV sandwich attacks remain a risk even when traders use private transaction routing. A study of Ethereum transactions from late 2024 identified 2,932 private sandwich attacks involving 3,126 victim transactions. The findings suggest that private routing can reduce visibility and make transaction ordering harder to control, but it does not guarantee protection.
A separate study of private Layer 2 mempools found that sandwich attacks were rare and generally unprofitable. The difference appears to depend on each network’s ordering system, builder market and ability to execute the attacker’s transactions atomically.
For traders, a profitable sandwich attack requires more than access to a pending transaction. The victim’s trade must be large relative to available liquidity, remain executable after the attacker moves the price, and generate enough revenue to cover pool fees and gas costs. Wide slippage limits increase the attack surface, while tighter minimum-return settings can cause the transaction to revert instead.
The article distinguishes between MEV mitigation, MEV protection, MEV resistance and sandwich immunity. Private routing and slippage controls generally reduce risk rather than eliminate it. Carbon DeFi’s maker orders are presented as a narrower form of sandwich immunity because the maker sets the executable price; the order either fills at that price or does not execute.
The legal status of some MEV activity also remains unsettled. In 2025, a US jury failed to reach a verdict in the case against Anton and James Peraire-Bueno, who were accused of extracting about $25 million from trading bots through Ethereum’s MEV-Boost infrastructure. The mistrial did not establish that the conduct was legal or that conventional sandwich attacks are categorically illegal.
Neutral
The expected market impact is neutral because the article presents no protocol exploit, token-specific event or immediate change to network fundamentals. Its main message is that MEV sandwich attacks remain an execution risk and that private routing provides mitigation rather than guaranteed protection.
In the short term, traders may respond by reducing slippage tolerance, using private RPC or relay services, splitting large swaps and avoiding shallow-liquidity pools. Such behavior could modestly reduce toxic flow and improve execution quality, but it could also increase failed transactions and reduce trading activity in volatile markets. The research showing 2,932 private attacks on Ethereum transactions may weaken confidence in broad MEV-protection claims, although it does not imply that Ethereum itself is compromised.
The Layer 2 findings provide a counterbalance: private mempools with weaker attacker control and less reliable ordering can make sandwiches rare and unprofitable. This could support adoption of specialized execution environments over time, but the effect is unlikely to create an immediate bullish or bearish move in ETH or DeFi tokens.
Long term, clearer disclosures around MEV protection, stronger slippage controls and execution models based on predefined prices could improve user confidence and market quality. The unresolved Peraire-Bueno legal case may also encourage regulators and protocols to clarify the boundary between arbitrage, transaction ordering and deceptive manipulation. Similar past MEV-related news has generally affected trading conditions and protocol design more than broad market direction, supporting a neutral classification.