What Is a “Race Attack” in the Context of Double-Spending?

A race attack is a type of double-spend attempt where an attacker quickly broadcasts two conflicting transactions to the network. The first transaction sends the funds to a merchant, and the second transaction sends the same funds back to the attacker's own address.

The goal is to have the second transaction confirmed by a miner before the first one. If the merchant accepts the zero-confirmation transaction before the network finalizes the conflicting one, the attack succeeds.