What Are Sandwich Attacks?
Sandwich attacks occur when a malicious validator or miner reorders transactions to profit from users making token swaps. This is common on Ethereum and other EVM-based blockchains because validators can prioritize, delay, or insert transactions at will.
The Root Cause: Account-Based Models
Ethereum uses an account-based model similar to traditional banking. Validators process transactions by mutating global account balances and smart contract states. Because of this centralized state access, validators can scan the mempool and manipulate transactions for profit.
This creates fertile ground for MEV (Maximal Extractable Value) and sandwich attacks. The transaction order becomes a high-stakes game, especially during DEX trades.
UTXO Model: Stateless, Parallel, Secure
In contrast, eCash (like Bitcoin) uses the UTXO (Unspent Transaction Output) model. Each transaction consumes specific inputs and creates new outputs, like cash changing hands. There is no global mutable state.
- No account balances
- No smart contract state mutations
- Each transaction is self-contained
This architecture makes it extremely difficult (if not impossible) for miners to reorder transactions for profit, because the system has no global state to manipulate.
Why eCash Doesn’t Suffer from Sandwich Attacks
eCash’s miners don’t select transactions based on potential arbitrage or MEV opportunities. Transactions are ordered in a neutral and deterministic way. There are no incentives or mechanisms to "front-run" or "sandwich" users.
Additionally, because eCash doesn’t run a shared state machine with global smart contracts, it inherently avoids the types of manipulation found on Ethereum and EVM chains.
Conclusion
While Ethereum and similar chains rely on global states and validator discretion—opening the door to MEV games—eCash’s UTXO model and Avalanche+PoW consensus provide a more secure, neutral, and user-respecting foundation.
If you're tired of MEV stealing your value, consider building and transacting on eCash.