Double Spend
Security● Common
An attack attempting to spend the same bitcoin twice. Bitcoin's proof-of-work consensus prevents this: only one version can be included in the canonical chain. Unconfirmed transactions are vulnerable; confirmations provide exponentially increasing security.
Technical Notes
Attack types: race attack (fast double-broadcast), Finney attack (pre-mined block), 51% attack (majority hashrate reorg). Defense: wait for confirmations, monitor mempool, use RBF detection. 6 confirmations makes reversal extremely expensive.
Metadata
Visibility: Public
Created:1/3/2026by System