![Crypto Terms Glossary: What is Finney Attack? Crypto Terms Glossary: What is Finney Attack?](/img/110/591/what-is-finney-attack-sm.webp)
A Finney attack is an attack where a miner pre-mines a transaction into a block from one wallet to another. Then, they use the first wallet to make a second transaction and broadcast the pre-mined block which has the first transaction. This requires a very specific sequence to work. This is only possible if the receiver of the transaction accepts an unconfirmed transaction.